Security Advisory

CVE-2026-50258

CVE vulnerability detail - eXtreme Datacenter Security Operations

Published 2026-06-05 10:31:39

Last updated 2026-07-15 00:47:05

Assigner redhat

CVSS score not scored

State PUBLISHED

Description

A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. The X server has multiple stack buffers sized XkbMaxShiftLevel * XkbNumKbdGroups but CheckKeyTypes() does not verify or clamp non-canonical key types to XkbMaxShiftLevel. A client can change key types to excessive shift levels and trigger stack overflows. This is caused by an incomplete fix of CVE-2025-26597. This may be used to crash the server, or for privilege escalation if the X server runs as root.

← Browse all CVEs View on cve.org ↗