USN-7234-3: Linux kernel (Azure) vulnerabilities

Publication date

4 February 2025

Overview

Several security issues were fixed in the Linux kernel.


Packages

Details

Ye Zhang and Nicolas Wu discovered that the io_uring subsystem in the Linux
kernel did not properly handle locking for rings with IOPOLL, leading to a
double-free vulnerability. A local attacker could use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2023-21400)

Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:

  • TTY drivers;
  • Netfilter;
  • Network traffic control;
  • VMware vSockets driver

Ye Zhang and Nicolas Wu discovered that the io_uring subsystem in the Linux
kernel did not properly handle locking for rings with IOPOLL, leading to a
double-free vulnerability. A local attacker could use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2023-21400)

Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:

  • TTY drivers;
  • Netfilter;
  • Network traffic control;
  • VMware vSockets driver

Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

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.

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

Ubuntu Release Package Version
20.04 focal linux-image-5.4.0-1143-azure –  5.4.0-1143.150
linux-image-azure-lts-20.04 –  5.4.0.1143.137
18.04 bionic linux-image-5.4.0-1143-azure –  5.4.0-1143.150~18.04.1  
linux-image-azure –  5.4.0.1143.150~18.04.1  

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.


Have additional questions?

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