A Linux kernel (OEM) security update has been released for Ubuntu Linux 20.04 LTS.

USN-5206-1: Linux kernel (OEM) vulnerability

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Ubuntu Security Notice USN-5206-1
January 05, 2022

linux-oem-5.14 vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS

Summary:

The system could be made to crash or run programs as an administrator.

Software Description:
- linux-oem-5.14: Linux kernel for OEM systems

Details:

Nadav Amit discovered that the hugetlb implementation in the Linux kernel
did not perform TLB flushes under certain conditions. A local attacker
could use this to leak or alter data from other processes that use huge
pages.

Update instructions:

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

Ubuntu 20.04 LTS:
linux-image-5.14.0-1013-oem 5.14.0-1013.13
linux-image-oem-20.04d 5.14.0.1013.13

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-5206-1
CVE-2021-4002

Package Information:
  https://launchpad.net/ubuntu/+source/linux-oem-5.14/5.14.0-1013.13