Use After Free Affecting libvirt package, versions <7.6.0-0ubuntu3


Severity

Recommended
low

Based on Ubuntu security rating.

Threat Intelligence

EPSS
1.22% (66th percentile)

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  • Snyk IDSNYK-UBUNTU2510-LIBVIRT-15735836
  • published21 Mar 2026
  • disclosed23 Aug 2022

Introduced: 23 Aug 2022

CVE-2021-3975  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Ubuntu:25.10 libvirt to version 7.6.0-0ubuntu3 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream libvirt package and not the libvirt package as distributed by Ubuntu. See How to fix? for Ubuntu:25.10 relevant fixed versions and status.

A use-after-free flaw was found in libvirt. The qemuMonitorUnregister() function in qemuProcessHandleMonitorEOF is called using multiple threads without being adequately protected by a monitor lock. This flaw could be triggered by the virConnectGetAllDomainStats API when the guest is shutting down. An unprivileged client with a read-only connection could use this flaw to perform a denial of service attack by causing the libvirt daemon to crash.

CVSS Base Scores

version 3.1