USN-6533-1: Linux kernel (OEM) vulnerabilities

5 December 2023

Several security issues were fixed in the Linux kernel.

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Releases

Packages

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)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

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Update instructions

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

Ubuntu 22.04

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.