A Linux kernel security update has been released for Ubuntu Linux 23.10.

[USN-6454-2] Linux kernel vulnerabilities

==========================================================================
Ubuntu Security Notice USN-6454-2
October 30, 2023

linux-aws, linux-azure, linux-gcp, linux-oracle, linux-raspi
vulnerabilities
==========================================================================

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

- Ubuntu 23.10

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-aws: Linux kernel for Amazon Web Services (AWS) systems
- linux-azure: Linux kernel for Microsoft Azure Cloud systems
- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems
- linux-oracle: Linux kernel for Oracle Cloud systems
- linux-raspi: Linux kernel for Raspberry Pi systems

Details:

Kyle Zeng discovered that the netfilter subsystem in the Linux kernel
contained a race condition in IP set operations in certain situations. A
local attacker could use this to cause a denial of service (system crash).
(CVE-2023-42756)

Alex Birnberg discovered that the netfilter subsystem in the Linux kernel
did not properly validate register length, leading to an out-of- bounds
write vulnerability. A local attacker could possibly use this to cause a
denial of service (system crash). (CVE-2023-4881)

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)

Kevin Rich discovered that the netfilter subsystem in the Linux kernel did
not properly handle removal of rules from chain bindings in certain
circumstances, leading to a use-after-free vulnerability. A local attacker
could possibly use this to cause a denial of service (system crash) or
execute arbitrary code. (CVE-2023-5197)

Update instructions:

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

Ubuntu 23.10:
linux-image-6.5.0-1006-raspi 6.5.0-1006.8
linux-image-6.5.0-1008-azure 6.5.0-1008.8
linux-image-6.5.0-1008-azure-fde 6.5.0-1008.8
linux-image-6.5.0-1008-gcp 6.5.0-1008.8
linux-image-6.5.0-1009-aws 6.5.0-1009.9
linux-image-6.5.0-1011-oracle 6.5.0-1011.11
linux-image-aws 6.5.0.1009.9
linux-image-azure 6.5.0.1008.10
linux-image-azure-fde 6.5.0.1008.10
linux-image-gcp 6.5.0.1008.8
linux-image-oracle 6.5.0.1011.11
linux-image-raspi 6.5.0.1006.7
linux-image-raspi-nolpae 6.5.0.1006.7

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-6454-2
https://ubuntu.com/security/notices/USN-6454-1
CVE-2023-42756, CVE-2023-4881, CVE-2023-4921, CVE-2023-5197

Package Information:
https://launchpad.net/ubuntu/+source/linux-aws/6.5.0-1009.9
https://launchpad.net/ubuntu/+source/linux-azure/6.5.0-1008.8
https://launchpad.net/ubuntu/+source/linux-gcp/6.5.0-1008.8
https://launchpad.net/ubuntu/+source/linux-oracle/6.5.0-1011.11
https://launchpad.net/ubuntu/+source/linux-raspi/6.5.0-1006.8