ID

VAR-202105-1451

CVE

CVE-2021-22543

TITLE

Red Hat Security Advisory 2021-3943-01

DESCRIPTION

An issue was discovered in Linux: KVM through Improper handling of VM_IO|VM_PFNMAP vmas in KVM can bypass RO checks and can lead to pages being freed while still accessible by the VMM and guest. This allows users with the ability to start and control a VM to read/write random pages of memory and can result in local privilege escalation. Arch Linux is an application system of Arch open source. A lightweight and flexible Linux® distribution that tries to keep it simple. These packages include redhat-release-virtualization-host. RHVH features a Cockpit user interface for monitoring the host's resources and performing administrative tasks. (BZ#2010171) 4. -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 ===================================================================== Red Hat Security Advisory Synopsis: Important: kernel-rt security and bug fix update Advisory ID: RHSA-2021:3088-01 Product: Red Hat Enterprise Linux Advisory URL: https://access.redhat.com/errata/RHSA-2021:3088 Issue date: 2021-08-10 CVE Names: CVE-2021-3609 CVE-2021-22543 CVE-2021-22555 ===================================================================== 1. Summary: An update for kernel-rt is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section. 2. Relevant releases/architectures: Red Hat Enterprise Linux Real Time (v. 8) - x86_64 Red Hat Enterprise Linux Real Time for NFV (v. 8) - x86_64 3. Description: The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements. Security Fix(es): * kernel: race condition in net/can/bcm.c leads to local privilege escalation (CVE-2021-3609) * kernel: Improper handling of VM_IO|VM_PFNMAP vmas in KVM can bypass RO checks (CVE-2021-22543) * kernel: out-of-bounds write in xt_compat_target_from_user() in net/netfilter/x_tables.c (CVE-2021-22555) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section. Bug Fix(es): * kernel-rt: update RT source tree to the RHEL-8.4.z source tree (BZ#1985050) * kernel-rt: Merge mm/memcg: Fix kmem_cache_alloc() performance regression (BZ#1987102) 4. Solution: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. 5. Package List: Red Hat Enterprise Linux Real Time for NFV (v. 8): Source: kernel-rt-4.18.0-305.12.1.rt7.84.el8_4.src.rpm x86_64: kernel-rt-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-core-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-core-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-debuginfo-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-devel-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-kvm-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-modules-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-modules-extra-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debuginfo-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debuginfo-common-x86_64-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-devel-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-kvm-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-modules-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-modules-extra-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm Red Hat Enterprise Linux Real Time (v. 8): Source: kernel-rt-4.18.0-305.12.1.rt7.84.el8_4.src.rpm x86_64: kernel-rt-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-core-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-core-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-debuginfo-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-devel-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-modules-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debug-modules-extra-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debuginfo-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-debuginfo-common-x86_64-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-devel-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-modules-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm kernel-rt-modules-extra-4.18.0-305.12.1.rt7.84.el8_4.x86_64.rpm These packages are GPG signed by Red Hat for security. Our key and details on how to verify the signature are available from https://access.redhat.com/security/team/key/ 7. Contact: The Red Hat security contact is <secalert@redhat.com>. More contact details at https://access.redhat.com/security/team/contact/ Copyright 2021 Red Hat, Inc. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIVAwUBYRJ8VtzjgjWX9erEAQipBA//VAUAxmSqXU2mTwkXN8IHvRc3ZHwnyZJS HHLYjeaXijPFjGor+JvG91BIuYiR35TVkz8R5H2H7p1X0SssSBA4PXRTb/awajd3 0XSoQmUFRJn2AZmGpWisqA2gvVCLSNwFZnkPIHev2lJN/RrnC90xdhVeYdk1Q0Mw r7LtMT4K/dI6kBPKboFdaEmuIP3E7OOrKE9YmZ2S5kPfDRP+CowIfFigpMNqWWv6 hyTo5MRzrteICyaI41WWX2kVW779F0GDKlTVTy1F45lLz1W/HLnavD9YB6pUhx5t u2UIP7W7thDNt9+ztSKvaDQSdAcTlnX9GpYWS5/4hSUONtJfJd7dHFY9RnVFfIrm 3xhox7E9oCMuRgaYDW96mSNR7Lt1Nbm70p2WOtjkKEvjzJ9njCxYCmozbIA8dUmt q2u+zPApt82GFV8ya2jjHOPmFL8oqOVnnxv4ofrm8HDubDuOoG4z4FkfXz2o/pn1 a5KN1QQjwSzFS/e8nGFwYlARyjEIz1D6+4fbdNNfNXCS5iBElQ1Gfk0Bh+9uMZiX kK67XL3UPS7ymSpyuE/h47JAFtCrVJ/JIWKpiNVFpPIY9lG/C7yMXMpJOTE+fb/b AnYMzfWHrkOdb2ks4DWW3826XLAWTMHZPdiT6yWzX4gnwTqdBgrBDlAKnVq6NnE9 HhmjU48kbcE= =I9nv -----END PGP SIGNATURE----- -- RHSA-announce mailing list RHSA-announce@redhat.com https://listman.redhat.com/mailman/listinfo/rhsa-announce . Description: Red Hat Advanced Cluster Management for Kubernetes 2.3.2 images Red Hat Advanced Cluster Management for Kubernetes provides the capabilities to address common challenges that administrators and site reliability engineers face as they work across a range of public and private cloud environments. Clusters and applications are all visible and managed from a single console—with security policy built in. See the following Release Notes documentation, which will be updated shortly for this release, for additional details about this release: https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_mana gement_for_kubernetes/2.3/html/release_notes/ Security: * nodejs-kind-of: ctorName in index.js allows external user input to overwrite certain internal attributes (CVE-2019-20149) Bugs: * RHACM 2.3.2 images (BZ# 1991623) 3. Solution: Before applying this update, make sure all previously released errata relevant to your system have been applied. Bugs fixed (https://bugzilla.redhat.com/): 1959721 - CVE-2019-20149 nodejs-kind-of: ctorName in index.js allows external user input to overwrite certain internal attributes 1991623 - RHACM 2.3.2 images 5. 8.1) - ppc64le, x86_64 3. Description: This is a kernel live patch module which is automatically loaded by the RPM post-install script to modify the code of a running kernel. ========================================================================== Ubuntu Security Notice USN-5070-1 September 08, 2021 linux, linux-aws, linux-aws-5.11, linux-azure, linux-azure-5.11, linux-gcp, linux-hwe-5.11, linux-kvm, linux-oracle, linux-oracle-5.11, linux-raspi vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 21.04 - Ubuntu 20.04 LTS Summary: Several security issues were fixed in the Linux kernel. Software Description: - linux: Linux kernel - linux-aws: Linux kernel for Amazon Web Services (AWS) systems - linux-azure: Linux kernel for Microsoft Azure Cloud systems - linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems - linux-kvm: Linux kernel for cloud environments - linux-oracle: Linux kernel for Oracle Cloud systems - linux-raspi: Linux kernel for Raspberry Pi (V8) systems - linux-aws-5.11: Linux kernel for Amazon Web Services (AWS) systems - linux-azure-5.11: Linux kernel for Microsoft Azure cloud systems - linux-hwe-5.11: Linux hardware enablement (HWE) kernel - linux-oracle-5.11: Linux kernel for Oracle Cloud systems Details: Maxim Levitsky and Paolo Bonzini discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel allowed a guest VM to disable restrictions on VMLOAD/VMSAVE in a nested guest. An attacker in a guest VM could use this to read or write portions of the host's physical memory. (CVE-2021-3656) Maxim Levitsky discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel did not properly prevent a guest VM from enabling AVIC in nested guest VMs. An attacker in a guest VM could use this to write to portions of the host's physical memory. (CVE-2021-3653) It was discovered that the Linux kernel did not properly enforce certain types of entries in the Secure Boot Forbidden Signature Database (aka dbx) protection mechanism. An attacker could use this to bypass UEFI Secure Boot restrictions. (CVE-2020-26541) It was discovered that the KVM hypervisor implementation in the Linux kernel did not properly perform reference counting in some situations, leading to a use-after-free vulnerability. An attacker who could start and control a VM could possibly use this to expose sensitive information or execute arbitrary code. (CVE-2021-22543) Norbert Slusarek discovered that the CAN broadcast manger (bcm) protocol implementation in the Linux kernel did not properly initialize memory in some situations. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2021-34693) Murray McAllister discovered that the joystick device interface in the Linux kernel did not properly validate data passed via an ioctl(). A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code on systems with a joystick device registered. (CVE-2021-3612) It was discovered that the KVM hypervisor implementation in the Linux kernel did not properly compute the access permissions for shadow pages in some situations. A local attacker could use this to cause a denial of service. (CVE-2021-38198) It was discovered that the perf subsystem in the Linux kernel for the PowerPC architecture contained a null pointer dereference in some situations. An attacker could use this to cause a denial of service (system crash). (CVE-2021-38200) Ben Greear discovered that the mac80211 subsystem in the Linux kernel contained a null pointer dereference in some situations. A physically proximate attacker could possibly use this to cause a denial of service (system crash). (CVE-2021-38206) It was discovered that the Xilinx LL TEMAC device driver in the Linux kernel did not properly calculate the number of buffers to be used in certain situations. A remote attacker could use this to cause a denial of service (system crash). (CVE-2021-38207) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 21.04: linux-image-5.11.0-1015-azure 5.11.0-1015.16 linux-image-5.11.0-1015-kvm 5.11.0-1015.16 linux-image-5.11.0-1017-aws 5.11.0-1017.18 linux-image-5.11.0-1017-oracle 5.11.0-1017.18 linux-image-5.11.0-1017-raspi 5.11.0-1017.18 linux-image-5.11.0-1017-raspi-nolpae 5.11.0-1017.18 linux-image-5.11.0-1018-gcp 5.11.0-1018.20 linux-image-5.11.0-34-generic 5.11.0-34.36 linux-image-5.11.0-34-generic-64k 5.11.0-34.36 linux-image-5.11.0-34-generic-lpae 5.11.0-34.36 linux-image-5.11.0-34-lowlatency 5.11.0-34.36 linux-image-aws 5.11.0.1017.18 linux-image-azure 5.11.0.1015.16 linux-image-gcp 5.11.0.1018.18 linux-image-generic 5.11.0.34.36 linux-image-generic-64k 5.11.0.34.36 linux-image-generic-lpae 5.11.0.34.36 linux-image-gke 5.11.0.1018.18 linux-image-kvm 5.11.0.1015.16 linux-image-lowlatency 5.11.0.34.36 linux-image-oem-20.04 5.11.0.34.36 linux-image-oracle 5.11.0.1017.18 linux-image-raspi 5.11.0.1017.15 linux-image-raspi-nolpae 5.11.0.1017.15 linux-image-virtual 5.11.0.34.36 Ubuntu 20.04 LTS: linux-image-5.11.0-1015-azure 5.11.0-1015.16~20.04.1 linux-image-5.11.0-1017-aws 5.11.0-1017.18~20.04.1 linux-image-5.11.0-1017-oracle 5.11.0-1017.18~20.04.1 linux-image-5.11.0-34-generic 5.11.0-34.36~20.04.1 linux-image-5.11.0-34-generic-64k 5.11.0-34.36~20.04.1 linux-image-5.11.0-34-generic-lpae 5.11.0-34.36~20.04.1 linux-image-5.11.0-34-lowlatency 5.11.0-34.36~20.04.1 linux-image-aws 5.11.0.1017.18~20.04.16 linux-image-generic-64k-hwe-20.04 5.11.0.34.36~20.04.13 linux-image-generic-hwe-20.04 5.11.0.34.36~20.04.13 linux-image-generic-lpae-hwe-20.04 5.11.0.34.36~20.04.13 linux-image-lowlatency-hwe-20.04 5.11.0.34.36~20.04.13 linux-image-oracle 5.11.0.1017.18~20.04.10 linux-image-virtual-hwe-20.04 5.11.0.34.36~20.04.13 After a standard system update you need to reboot your computer to make all the necessary changes. ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual, linux-powerpc), a standard system upgrade will automatically perform this as well. References: https://ubuntu.com/security/notices/USN-5070-1 CVE-2020-26541, CVE-2021-22543, CVE-2021-34693, CVE-2021-3612, CVE-2021-3653, CVE-2021-3656, CVE-2021-38198, CVE-2021-38200, CVE-2021-38206, CVE-2021-38207 Package Information: https://launchpad.net/ubuntu/+source/linux/5.11.0-34.36 https://launchpad.net/ubuntu/+source/linux-aws/5.11.0-1017.18 https://launchpad.net/ubuntu/+source/linux-azure/5.11.0-1015.16 https://launchpad.net/ubuntu/+source/linux-gcp/5.11.0-1018.20 https://launchpad.net/ubuntu/+source/linux-kvm/5.11.0-1015.16 https://launchpad.net/ubuntu/+source/linux-oracle/5.11.0-1017.18 https://launchpad.net/ubuntu/+source/linux-raspi/5.11.0-1017.18 https://launchpad.net/ubuntu/+source/linux-aws-5.11/5.11.0-1017.18~20.04.1 https://launchpad.net/ubuntu/+source/linux-azure-5.11/5.11.0-1015.16~20.04.1 https://launchpad.net/ubuntu/+source/linux-hwe-5.11/5.11.0-34.36~20.04.1 https://launchpad.net/ubuntu/+source/linux-oracle-5.11/5.11.0-1017.18~20.04.1

AFFECTED PRODUCTS

CVSS

PROBLEMTYPE DATA

TYPE

bypass

PATCH

EXTERNAL IDS

REFERENCES

CREDITS

Red Hat

SOURCES

LAST UPDATE DATE

2026-04-18T21:55:29.408000+00:00

SOURCES UPDATE DATE

SOURCES RELEASE DATE