==========================================================================
Ubuntu Security Notice USN-6497-1
November 21, 2023

linux-oem-6.1 vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 22.04 LTS

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-oem-6.1: Linux kernel for OEM systems

Details:

Maxim Levitsky discovered that the KVM nested virtualization (SVM)
implementation for AMD processors in the Linux kernel did not properly
handle x2AVIC MSRs. An attacker in a guest VM could use this to cause a
denial of service (host kernel crash). (CVE-2023-5090)

Alon Zahavi discovered that the NVMe-oF/TCP subsystem in the Linux kernel
did not properly handle queue initialization failures in certain
situations, leading to a use-after-free vulnerability. A remote attacker
could use this to cause a denial of service (system crash) or possibly
execute arbitrary code. (CVE-2023-5178)

Budimir Markovic discovered that the perf subsystem in the Linux kernel
did not properly handle event groups, leading to an out-of-bounds write
vulnerability. A local attacker could use this to cause a denial of
service (system crash) or possibly execute arbitrary code. (CVE-2023-5717)

Update instructions:

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

Ubuntu 22.04 LTS:
   linux-image-6.1.0-1026-oem      6.1.0-1026.26
   linux-image-oem-22.04           6.1.0.1026.27
   linux-image-oem-22.04a          6.1.0.1026.27
   linux-image-oem-22.04b          6.1.0.1026.27
   linux-image-oem-22.04c          6.1.0.1026.27

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-6497-1
   CVE-2023-5090, CVE-2023-5178, CVE-2023-5717

Package Information:
   https://launchpad.net/ubuntu/+source/linux-oem-6.1/6.1.0-1026.26