CVE-2026-33999

A flaw was found in the X.Org X server. This integer underflow vulnerability, specifically in the XKB compatibility map handling, allows an attacker with local or remote X11 server access to trigger a buffer read overrun. This can lead to memory-safety violations and potentially a denial of service (DoS) or other severe impacts.

Credits

Red Hat would like to thank Jan-Niklas Sohn (TrendAI Zero Day Initiative) for reporting this issue.

References