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.
References
Configurations
Configuration 1 (hide)
|
History
No history.
Information
Published : 2026-06-05 12:16
Updated : 2026-08-05 13:23
NVD link : CVE-2026-50258
Mitre link : CVE-2026-50258
CVE.ORG link : CVE-2026-50258
JSON object : View
Products Affected
x.org
- x_server
- xwayland
redhat
- enterprise_linux
CWE
CWE-121
Stack-based Buffer Overflow
