CVE-2026-50260
Published:June 05, 2026
Updated:June 07, 2026
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.
Affected Packages
https://gitlab.freedesktop.org/xorg/xserver.git (SCM_GIT):
Affected version(s) >=add-Xi <xwayland-24.1.12Fix Suggestion:
Update to version xwayland-24.1.12https://gitlab.freedesktop.org/xorg/xserver.git (SCM_GIT):
Affected version(s) >=add-Xi <xorg-server-21.1.23Fix Suggestion:
Update to version xorg-server-21.1.23Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.5
Attack Vector
LOCAL
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.8
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Weakness Type (CWE)
Use After Free
EPSS
Base Score:
0.01