==========================================================================
Ubuntu Security Notice USN-6461-1
October 31, 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:

Yu Hao discovered that the UBI driver in the Linux kernel did not properly
check for MTD with zero erasesize during device attachment. A local
privileged attacker could use this to cause a denial of service (system
crash). (CVE-2023-31085)

Marek Marczykowski-Górecki discovered that the Xen event channel
infrastructure implementation in the Linux kernel contained a race
condition. An attacker in a guest VM could possibly use this to cause a
denial of service (paravirtualized device unavailability). (CVE-2023-34324)

Lucas Leong discovered that the netfilter subsystem in the Linux kernel did
not properly validate some attributes passed from userspace. A local
attacker could use this to cause a denial of service (system crash) or
possibly expose sensitive information (kernel memory). (CVE-2023-39189)

Bien Pham discovered that the netfiler subsystem in the Linux kernel
contained a race condition, leading to a use-after-free vulnerability. A
local user could use this to cause a denial of service (system crash) or
possibly execute arbitrary code. (CVE-2023-4244)

Kyle Zeng discovered that the IPv4 implementation in the Linux kernel did
not properly handle socket buffers (skb) when performing IP routing in
certain circumstances, leading to a null pointer dereference vulnerability.
A privileged attacker could use this to cause a denial of service (system
crash). (CVE-2023-42754)

It was discovered that the Quick Fair Queueing scheduler implementation in
the Linux kernel did not properly handle network packets in certain
conditions, leading to a use after free vulnerability. A local attacker
could use this to cause a denial of service (system crash) or possibly
execute arbitrary code. (CVE-2023-4921)

It was discovered that the SMB network file sharing protocol implementation
in the Linux kernel did not properly handle certain error conditions,
leading to a use-after-free vulnerability. A local attacker could use this
to cause a denial of service (system crash) or possibly execute arbitrary
code. (CVE-2023-5345)

Update instructions:

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

Ubuntu 22.04 LTS:
   linux-image-6.1.0-1025-oem      6.1.0-1025.25
   linux-image-oem-22.04           6.1.0.1025.26
   linux-image-oem-22.04a          6.1.0.1025.26
   linux-image-oem-22.04b          6.1.0.1025.26
   linux-image-oem-22.04c          6.1.0.1025.26

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-6461-1
   CVE-2023-31085, CVE-2023-34324, CVE-2023-39189, CVE-2023-4244,
   CVE-2023-42754, CVE-2023-4921, CVE-2023-5345

Package Information:
   https://launchpad.net/ubuntu/+source/linux-oem-6.1/6.1.0-1025.25