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.
History

Fri, 05 Jun 2026 12:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

threat_severity

Important


Fri, 05 Jun 2026 11:45:00 +0000

Type Values Removed Values Added
Description 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.
Title Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: use-after-free in freecounter()
First Time appeared Redhat
Redhat enterprise Linux
Weaknesses CWE-416
CPEs cpe:/o:redhat:enterprise_linux:10
cpe:/o:redhat:enterprise_linux:6
cpe:/o:redhat:enterprise_linux:7
cpe:/o:redhat:enterprise_linux:8
cpe:/o:redhat:enterprise_linux:9
Vendors & Products Redhat
Redhat enterprise Linux
References
Metrics cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2026-06-05T10:36:30.319Z

Reserved: 2026-06-04T14:55:24.011Z

Link: CVE-2026-50260

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-06-05T12:16:39.430

Modified: 2026-06-05T12:16:39.430

Link: CVE-2026-50260

cve-icon Redhat

Severity : Important

Publid Date: 2026-06-02T00:00:00Z

Links: CVE-2026-50260 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-06-05T12:30:40Z