X.org Xserver & Xwayland Security Advisory: UAF and Overflow CVEs

X.org Security Advisory: Multiple Security Issues Vulnerability Overview Multiple security issues have been identified in the X.org server and Xwayland implementations, involving the following three vulnerabilities: 1. CVE-2025-02229: During the creation of an XPresentNotify fixup, when processing and adding notifications, if an error occurs, a dangling pointer may be left on the error code path, leading to a use-after-free vulnerability when the notification structure is later destroyed. 2. CVE-2025-02230: When removing a client’s Xkb resources, the function frees the data associated with the device but does not free the data associated with the resource. Consequently, when the client terminates, the resource deletion function triggers a use-after-free vulnerability. 3. CVE-2025-02231: In the Xkb extension , the structure uses unsigned short integers to store certain values, but does not check whether the sum of input data could exceed the maximum unsigned short value, resulting in a value overflow vulnerability. Impact Scope X.org X server versions earlier than 21.1.18 Xwayland versions earlier than 24.1.9 Remediation X.org X server: Upgrade to version 21.1.18 or later Xwayland: Upgrade to version 24.1.9 or later Fix Links CVE-2025-02229: Fix link CVE-2025-02230: Fix link CVE-2025-02231: Fix link Discoverer Discovered by Jan-Niklas Sohn in collaboration with Trend Micro Zero Day Initiative Additional Information Advisory date: October 28, 2025 Mailing list: xorg-announce

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X.org Xserver & Xwayland Security Advisory: UAF and Overflow CVEs