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

USN-5485-2: Linux kernel (OEM) vulnerabilities

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Ubuntu Security Notice USN-5485-2
July 01, 2022

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

- Ubuntu 20.04 LTS

Summary:

Several security issues were mitigated in the Linux kernel.

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

Details:

It was discovered that some Intel processors did not completely perform
cleanup actions on multi-core shared buffers. A local attacker could
possibly use this to expose sensitive information. (CVE-2022-21123)

It was discovered that some Intel processors did not completely perform
cleanup actions on microarchitectural fill buffers. A local attacker could
possibly use this to expose sensitive information. (CVE-2022-21125)

It was discovered that some Intel processors did not properly perform
cleanup during specific special register write operations. A local attacker
could possibly use this to expose sensitive information. (CVE-2022-21166)

Update instructions:

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

Ubuntu 20.04 LTS:
linux-image-5.14.0-1044-oem 5.14.0-1044.49
linux-image-oem-20.04 5.14.0.1044.40
linux-image-oem-20.04b 5.14.0.1044.40
linux-image-oem-20.04c 5.14.0.1044.40
linux-image-oem-20.04d 5.14.0.1044.40

Please note that fully mitigating processor vulnerabilities requires
corresponding processor microcode/firmware updates.

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-5485-2
  https://ubuntu.com/security/notices/USN-5485-1
CVE-2022-21123, CVE-2022-21125, CVE-2022-21166

Package Information:
  https://launchpad.net/ubuntu/+source/linux-oem-5.14/5.14.0-1044.49