CVE-2026-56000

Local attackers with a X connection able to provide GLX commit to the X server xorg-server before 21.2.24 and xwayland before 24.1.13 could cause a Heap Use After Free, due to CommonMakeCurrent() pointing into potentially reallocated memory.

• xorg-server 2:21.1.24-1 (bug https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1141703)
• xwayland 2:24.1.13-1 [trixie] - xwayland (Minor issue; Xwayland shouldn't be running as root) [bookworm] - xwayland (Minor issue; Xwayland shouldn't be running as root) https://www.openwall.com/lists/oss-security/2026/07/08/2 Fixed by: https://gitlab.freedesktop.org/xorg/xserver/-/commit/2779affbdb4354e894f490e56f962527d6125043