Xwayland: xorg: x.org x server: information disclosure and denial of service via out-of-bounds read in xkb geometry processing.

Summary

A flaw was found in the X.Org X server. This out-of-bounds read vulnerability in the XKB geometry processing, specifically within the `CheckSetGeom()` and `XkbAddGeomKeyAlias` functions, allows an attacker to read uninitialized or out-of-bounds memory. An attacker with a connection to the X11 server, either locally or remotely, can exploit this without user interaction. This could lead to the disclosure of memory contents or cause a denial of service by crashing the server.

Timeline

1. May 5, 2026, 2:41 PM UTCCVE published
2. May 5, 2026, 6:51 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. Jun 8, 2026, 3:30 AM UTCRecord last updated

Affected versions

• xorg-x11-server-Xwayland

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

• xorg-x11-server

  Version range not reported

• tigervnc

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

• xorg-x11-server

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

• xorg-x11-server

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

• xorg-x11-server

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

• xorg-x11-server

  Version range not reported

• tigervnc

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

• xorg-x11-server

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

• xorg-x11-server

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

• xorg-x11-server

  Version range not reported

• tigervnc

  Version range not reported

• xorg-x11-server

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

• xorg-x11-server

  Version range not reported

• xorg-x11-server-Xwayland

  Version range not reported

References 25