==========================================================================
Ubuntu Security Notice USN-6533-1
December 05, 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:

Tom Dohrmann discovered that the Secure Encrypted Virtualization (SEV)
implementation for AMD processors in the Linux kernel contained a race
condition when accessing MMIO registers. A local attacker in a SEV guest VM
could possibly use this to cause a denial of service (system crash) or
possibly execute arbitrary code. (CVE-2023-46813)

It was discovered that the io_uring subsystem in the Linux kernel contained
a race condition, leading to a null pointer dereference vulnerability. A
local attacker could use this to cause a denial of service (system crash).
(CVE-2023-46862)

Update instructions:

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

Ubuntu 22.04 LTS:
   linux-image-6.1.0-1027-oem      6.1.0-1027.27
   linux-image-oem-22.04           6.1.0.1027.28
   linux-image-oem-22.04a          6.1.0.1027.28
   linux-image-oem-22.04b          6.1.0.1027.28
   linux-image-oem-22.04c          6.1.0.1027.28

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-6533-1
   CVE-2023-46813, CVE-2023-46862

Package Information:
   https://launchpad.net/ubuntu/+source/linux-oem-6.1/6.1.0-1027.27