ID

VAR-200702-0313

CVE

CVE-2007-0917

TITLE

Cisco IOS of IPS Detection evasion vulnerability in function

DESCRIPTION

The Intrusion Prevention System (IPS) feature for Cisco IOS 12.4XE to 12.3T allows remote attackers to bypass IPS signatures that use regular expressions via fragmented packets. Cisco IOS is prone to a security-bypass vulnerability and a denial-of-service vulnerability. An attacker could exploit the security-bypass issue to send malicious data to computers that would otherwise be protected by signature inspection. An attacker could exploit the denial-of-service vulnerability to crash affected devices, denying service to legitimate users. Several vulnerabilities exist in the IOS IPS function, and only IOS images that include the IPS function are affected by these vulnerabilities. All IP protocols (such as TCP, UDP, ICMP) are affected by this vulnerability. ATOMIC.TCP Regular Expression Denial of Service Vulnerability+------------------------------------------- -------------------- Certain network communications may trigger IPS signatures using the regular expression capabilities of the ATOMIC.TCP signature engine, resulting in denial of service and interruption of network communications. ---------------------------------------------------------------------- Secunia is proud to announce the availability of the Secunia Software Inspector. The Secunia Software Inspector is a free service that detects insecure versions of software that you may have installed in your system. When insecure versions are detected, the Secunia Software Inspector also provides thorough guidelines for updating the software to the latest secure version from the vendor. Try it out online: http://secunia.com/software_inspector/ ---------------------------------------------------------------------- TITLE: Cisco IOS IPS Security Bypass and Denial of Service SECUNIA ADVISORY ID: SA24142 VERIFY ADVISORY: http://secunia.com/advisories/24142/ CRITICAL: Moderately critical IMPACT: Security Bypass, DoS WHERE: >From remote OPERATING SYSTEM: Cisco IOS R12.x http://secunia.com/product/50/ Cisco IOS 12.x http://secunia.com/product/182/ DESCRIPTION: Two vulnerabilities have been reported in Cisco IOS, which can be exploited by malicious people to bypass certain security restrictions or cause a DoS (Denial of Service). This can be exploited to bypass the detection mechanism by sending specially crafted, fragmented IP packets. 2) An error exists within the ATOMIC.TCP scanning mechanism and signatures, which use regular expressions (e.g. Signature 3123.0 for Netbus Pro Traffic). This can be exploited to crash a device by producing specially crafted network traffic. SOLUTION: See the vendor advisory for a patch matrix and workarounds. PROVIDED AND/OR DISCOVERED BY: Reported by the vendor ORIGINAL ADVISORY: http://www.cisco.com/warp/public/707/cisco-sa-20070213-iosips.shtml http://www.cisco.com/en/US/products/products_security_response09186a00807e0a5e.html ---------------------------------------------------------------------- About: This Advisory was delivered by Secunia as a free service to help everybody keeping their systems up to date against the latest vulnerabilities. Subscribe: http://secunia.com/secunia_security_advisories/ Definitions: (Criticality, Where etc.) http://secunia.com/about_secunia_advisories/ Please Note: Secunia recommends that you verify all advisories you receive by clicking the link. Secunia NEVER sends attached files with advisories. Secunia does not advise people to install third party patches, only use those supplied by the vendor. ---------------------------------------------------------------------- Unsubscribe: Secunia Security Advisories http://secunia.com/sec_adv_unsubscribe/?email=packet%40packetstormsecurity.org ----------------------------------------------------------------------

AFFECTED PRODUCTS

CVSS

PROBLEMTYPE DATA

THREAT TYPE

remote

TYPE

other

CONFIGURATIONS

PATCH

EXTERNAL IDS

REFERENCES

CREDITS

Cisco Security bulletin

SOURCES

LAST UPDATE DATE

2025-04-10T23:16:51.584000+00:00

SOURCES UPDATE DATE

SOURCES RELEASE DATE