CVE-2026-50258
HIGH SEVERITYCVSS Score & Metrics
Base Score
7.8 / 10
Vector String
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Vulnerability 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.
Vulnerability Details
Published Date
Last Modified
CWE ID
CWE-121
Source
NVD
Vendor
Red Hat
Product
Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9
External References
- https://access.redhat.com/security/cve/CVE-2026-50258
- https://bugzilla.redhat.com/show_bug.cgi?id=2485383
- https://gitlab.freedesktop.org/xorg/xserver/-/commit/543e108516428fc8c3bea91d6563ad266f9a801e
- https://lists.x.org/archives/xorg-announce/2026-June/003702.html
- https://redhat.atlassian.net/browse/PSIRTSUPT-16950
Discussion (0)
Add Comment
No comments yet. Be the first!