1. Ubuntu Security Notices
  2. USN-5161-1

USN-5161-1: Linux kernel vulnerabilities

Publication date

30 November 2021

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

Details

Ilja Van Sprundel discovered that the SCTP implementation in the Linux
kernel did not properly perform size validations on incoming packets in
some situations. An attacker could possibly use this to expose sensitive
information (kernel memory). (CVE-2021-3655)

It was discovered that the AMD Cryptographic Coprocessor (CCP) driver in
the Linux kernel did not properly deallocate memory in some error
conditions. A local attacker could use this to cause a denial of service
(memory exhaustion). (CVE-2021-3744, CVE-2021-3764)

It was discovered that the Aspeed Low Pin Count (LPC) Bus Controller
implementation in the Linux kernel did not properly perform boundary checks
in some situations, allowing out-of-bounds write access. A local attacker
could use this to cause a denial of service (system crash) or possibly
execute...

Ilja Van Sprundel discovered that the SCTP implementation in the Linux
kernel did not properly perform size validations on incoming packets in
some situations. An attacker could possibly use this to expose sensitive
information (kernel memory). (CVE-2021-3655)

It was discovered that the AMD Cryptographic Coprocessor (CCP) driver in
the Linux kernel did not properly deallocate memory in some error
conditions. A local attacker could use this to cause a denial of service
(memory exhaustion). (CVE-2021-3744, CVE-2021-3764)

It was discovered that the Aspeed Low Pin Count (LPC) Bus Controller
implementation in the Linux kernel did not properly perform boundary checks
in some situations, allowing out-of-bounds write access. A local attacker
could use this to cause a denial of service (system crash) or possibly
execute arbitrary code. In Ubuntu, this issue only affected systems running
armhf kernels. (CVE-2021-42252)

Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

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.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
21.04 hirsute linux-image-5.11.0-41-generic-64k –  5.11.0-41.45
linux-image-5.11.0-1022-oracle –  5.11.0-1022.23
linux-image-virtual –  5.11.0.41.42
linux-image-generic-64k –  5.11.0.41.42
linux-image-generic –  5.11.0.41.42
linux-image-aws –  5.11.0.1022.23
linux-image-5.11.0-41-generic-lpae –  5.11.0-41.45
linux-image-5.11.0-1022-aws –  5.11.0-1022.23
linux-image-5.11.0-1023-raspi-nolpae –  5.11.0-1023.25
linux-image-5.11.0-41-generic –  5.11.0-41.45
linux-image-5.11.0-41-lowlatency –  5.11.0-41.45
linux-image-azure –  5.11.0.1022.23
linux-image-5.11.0-1022-azure –  5.11.0-1022.23
linux-image-raspi-nolpae –  5.11.0.1023.21
linux-image-oem-20.04 –  5.11.0.41.42
linux-image-gke –  5.11.0.1023.23
linux-image-gcp –  5.11.0.1023.23
linux-image-oracle –  5.11.0.1022.23
linux-image-5.11.0-1020-kvm –  5.11.0-1020.22
linux-image-raspi –  5.11.0.1023.21
linux-image-5.11.0-1023-raspi –  5.11.0-1023.25
linux-image-kvm –  5.11.0.1020.21
linux-image-5.11.0-1023-gcp –  5.11.0-1023.25
linux-image-generic-lpae –  5.11.0.41.42
linux-image-lowlatency –  5.11.0.41.42
20.04 focal linux-image-5.11.0-41-lowlatency –  5.11.0-41.45~20.04.1
linux-image-5.11.0-41-generic-64k –  5.11.0-41.45~20.04.1
linux-image-virtual-hwe-20.04 –  5.11.0.41.45~20.04.19
linux-image-aws –  5.11.0.1022.23~20.04.21
linux-image-5.11.0-41-generic-lpae –  5.11.0-41.45~20.04.1
linux-image-lowlatency-hwe-20.04 –  5.11.0.41.45~20.04.19
linux-image-generic-hwe-20.04 –  5.11.0.41.45~20.04.19
linux-image-5.11.0-1022-aws –  5.11.0-1022.23~20.04.1
linux-image-5.11.0-1022-oracle –  5.11.0-1022.23~20.04.1
linux-image-5.11.0-41-generic –  5.11.0-41.45~20.04.1
linux-image-azure –  5.11.0.1022.23~20.04.22
linux-image-5.11.0-1022-azure –  5.11.0-1022.23~20.04.1
linux-image-5.11.0-1023-gcp –  5.11.0-1023.25~20.04.1
linux-image-gcp –  5.11.0.1023.25~20.04.22
linux-image-oracle –  5.11.0.1022.23~20.04.15
linux-image-generic-64k-hwe-20.04 –  5.11.0.41.45~20.04.19
linux-image-generic-lpae-hwe-20.04 –  5.11.0.41.45~20.04.19

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References

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