Use After Free Affecting xorg-server package, versions <2:21.1.12-1ubuntu1


Severity

Recommended
medium

Based on Ubuntu security rating.

Threat Intelligence

EPSS
1.86% (78th percentile)

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  • Snyk IDSNYK-UBUNTU2510-XORGSERVER-15741403
  • published21 Mar 2026
  • disclosed5 Apr 2024

Introduced: 5 Apr 2024

CVE-2024-31083  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Ubuntu:25.10 xorg-server to version 2:21.1.12-1ubuntu1 or higher.

NVD Description

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

A use-after-free vulnerability was found in the ProcRenderAddGlyphs() function of Xorg servers. This issue occurs when AllocateGlyph() is called to store new glyphs sent by the client to the X server, potentially resulting in multiple entries pointing to the same non-refcounted glyphs. Consequently, ProcRenderAddGlyphs() may free a glyph, leading to a use-after-free scenario when the same glyph pointer is subsequently accessed. This flaw allows an authenticated attacker to execute arbitrary code on the system by sending a specially crafted request.

References

CVSS Base Scores

version 3.1