CVE-2026-50260
HIGH
NVD
CVSS Score
7.8
Severity
HIGH
Published
Jun 05, 2026
Vendor
unknown
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.
References
- https://access.redhat.com/security/cve/CVE-2026-50260
- https://bugzilla.redhat.com/show_bug.cgi?id=2485385
- https://gitlab.freedesktop.org/xorg/xserver/-/commit/f5abfb61994471023d8c6470428c8e30c411cc0b
- https://lists.x.org/archives/xorg-announce/2026-June/003702.html
- https://redhat.atlassian.net/browse/PSIRTSUPT-16950