Two more security issues were made public today concerning the X.Org Server codebase and in turn XWayland also being affected.

The Trend Micro Zero Day Initiative continues to be relentless in uncovering new X.Org Server security vulnerabilities in recent years. Assisted by Claude Opus 4.6, these latest security woes are now resolved.

Peter Hutterer of Red Hat just announced CVE-2026-55999 as a buffer overflow in the font code for GLAMOR as well as CVE-2026-56000 as a use-after-free in the GLX code path. More details on these latest X.Org code vulnerabilities can be found via today's [1]disclosure .

In turn [2]XWayland 24.1.13 is now available with these fixes plus a few other fixes too. Not yet tagged but X.Org Server 21.1.24 is also expected soon with these security fixes.

Update: [3]X.Org Server 21.24 is now available with these latest security fixes.



[1] https://lists.x.org/archives/xorg-announce/2026-July/003716.html

[2] https://lists.x.org/archives/xorg/2026-July/062256.html

[3] https://lists.x.org/archives/xorg-announce/2026-July/003718.html