Heap-based Buffer Overflow Affecting xorg-server package, versions <21.1.24-r0


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.27% (19th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-XORGSERVER-18391945
  • published29 Jul 2026
  • disclosed8 Jul 2026

Introduced: 8 Jul 2026

CVE-2026-55999  (opens in a new tab)
CWE-122  (opens in a new tab)

How to fix?

Upgrade Chainguard xorg-server to version 21.1.24-r0 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 Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

Local attackers with a X connection able to provide PCX fonts to the X server xorg-server before 21.2.24 and xwayland before 24.1.13 could cause a heap buffer overflow via SetFont due to missing glyph boundary checks.

CVSS Base Scores

version 3.1