====================================================================== X.Org Security Advisory: October 28, 2025
Issues in X.Org X server prior to 21.1.18 and Xwayland prior to 24.1.8 ====================================================================== Multiple issues have been found in the X server and Xwayland implementations published by X.Org for which we are releasing security fixes for in xorg-server-21.1.19 and xwayland-24.1.9. 1) CVE-2025-62229: Use-after-free in XPresentNotify structures creation Using the X11 Present extension, when processing and adding the notifications after presenting a pixmap, if an error occurs, a dangling pointer may be left in the error code path of the function causing a use-after-free when eventually destroying the notification structures later. Introduced in: Xorg 1.15 Fixed in: xorg-server-21.1.19 and xwayland-24.1.9 Fix: https://gitlab.freedesktop.org/xorg/xserver/-/commit/5a4286b1 Found by: Jan-Niklas Sohn working with Trend Micro Zero Day Initiative. 2) CVE-2025-62230: Use-after-free in Xkb client resource removal When removing the Xkb resources for a client, the function XkbRemoveResourceClient() will free the XkbInterest data associated with the device, but not the resource associated with it. As a result, when the client terminates, the resource delete function triggers a use-after-free. Introduced in: X11R6 Fixed in: xorg-server-21.1.19 and xwayland-24.1.9 Fix: https://gitlab.freedesktop.org/xorg/xserver/-/commit/99790a2c https://gitlab.freedesktop.org/xorg/xserver/-/commit/10c94238 Found by: Jan-Niklas Sohn working with Trend Micro Zero Day Initiative. 3) CVE-2025-62231: Value overflow in Xkb extension XkbSetCompatMap() The XkbCompatMap structure stores some of its values using an unsigned short, but fails to check whether the sum of the input data might overflow the maximum unsigned short value. Introduced in: X11R6 Fixed in: xorg-server-21.1.19 and xwayland-24.1.9 Fix: https://gitlab.freedesktop.org/xorg/xserver/-/commit/475d9f49 Found by: Jan-Niklas Sohn working with Trend Micro Zero Day Initiative.------------------------------------------------------------------------
X.Org thanks all of those who reported and fixed these issues, and those who helped with the review and release of this advisory and these fixes.
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