USN-8831-1: libvirt vulnerabilities

Publication date

28 September 2026

Overview

Several security issues were fixed in libvirt.


Packages

  • libvirt - Libvirt virtualization toolkit

Details

It was discovered that libvirt had an integer overflow vulnerability in
the NodeGetFreePages RPC handler. A local attacker could possibly use
this issue to cause a denial of service or execute arbitrary code.
(CVE-2026-18917)

It was discovered that libvirt did not correctly handle symbolic links
when changing ownership of the TPM emulator log file. A local attacker
with access to the swtpm account could possibly use this issue to cause libvirt
to change the ownership of an arbitrary file. (CVE-2026-77159)

It was discovered that libvirt had an integer overflow vulnerability in
the NodeGetFreePages RPC handler. A local attacker could possibly use
this issue to cause a denial of service or execute arbitrary code.
(CVE-2026-18917)

It was discovered that libvirt did not correctly handle symbolic links
when changing ownership of the TPM emulator log file. A local attacker
with access to the swtpm account could possibly use this issue to cause libvirt
to change the ownership of an arbitrary file. (CVE-2026-77159)

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.

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


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