Use After Free Affecting xorg-server package, versions <2:21.1.23-1


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.15% (5th percentile)

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  • Snyk IDSNYK-DEBIANUNSTABLE-XORGSERVER-17192501
  • published5 Jun 2026
  • disclosed5 Jun 2026

Introduced: 5 Jun 2026

CVE-2026-50260  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Debian:unstable xorg-server to version 2:21.1.23-1 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 Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

A use-after-free flaw was found in the X.Org X server and Xwayland in FreeCounter(). A client that sets up multiple SyncCounters and awaits on those triggers can trigger a use-after-free when destroying those counters via a second client connection. This may be used to crash the server, or for privilege escalation if the X server runs as root.

References

CVSS Base Scores

version 3.1