A Linux kernel security update has been released for Ubuntu Linux 14.04 LTS.

[USN-6341-1] Linux kernel vulnerabilities

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Ubuntu Security Notice USN-6341-1
September 06, 2023

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

- Ubuntu 14.04 LTS (Available with Ubuntu Pro)

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux: Linux kernel

Details:

Jordy Zomer and Alexandra Sandulescu discovered that syscalls invoking the
do_prlimit() function in the Linux kernel did not properly handle
speculative execution barriers. A local attacker could use this to expose
sensitive information (kernel memory). (CVE-2023-0458)

It was discovered that a use-after-free vulnerability existed in the IEEE
1394 (Firewire) implementation in the Linux kernel. A privileged attacker
could use this to cause a denial of service (system crash) or possibly
execute arbitrary code. (CVE-2023-3159)

It was discovered that the virtual terminal driver in the Linux kernel
contained a use-after-free vulnerability. A local attacker could use this
to cause a denial of service (system crash) or possibly expose sensitive
information (kernel memory). (CVE-2023-3567)

It was discovered that the Quick Fair Queueing network scheduler
implementation in the Linux kernel contained 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-2023-3611)

It was discovered that the network packet classifier with
netfilter/firewall marks implementation in the Linux kernel did not
properly handle reference counting, 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-2023-3776)

Update instructions:

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

Ubuntu 14.04 LTS (Available with Ubuntu Pro):
linux-image-3.13.0-193-generic 3.13.0-193.244
linux-image-3.13.0-193-lowlatency 3.13.0-193.244
linux-image-generic 3.13.0.193.203
linux-image-generic-lts-trusty 3.13.0.193.203
linux-image-lowlatency 3.13.0.193.203
linux-image-server 3.13.0.193.203
linux-image-virtual 3.13.0.193.203

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-6341-1
CVE-2023-0458, CVE-2023-3159, CVE-2023-3567, CVE-2023-3611,
CVE-2023-3776