CVE-2026-50259
Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: stack buffer overflow in xkb setmap request via mapwidths indexing
Description
A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. _XkbSetMapChecks() declares a fixed-size stack buffer mapWidths[256] indexed by key type index. The helper function CheckKeyTypes() writes to this buffer at a client-controlled offset, allowing a stack buffer overflow. This may be used to crash the server, or for privilege escalation if the X server runs as root.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:LAttack VectorLocal
AC:LAttack ComplexityLow
PR:LPrivileges RequiredLow
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:HConfidentialityHigh
I:HIntegrityHigh
A:HAvailabilityHigh
Weaknesses
Affected Products
Red Hat Inc.
commercial·USaka Red Hat, redhat
x.org
oss-project·US
Сообщество свободного программного обеспечения
oss-projectaka fsf
X.Org Foundation
oss-project·USaka xorg-server, xlib, libx11
and 9 more affected products View all →
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.
MITRE ATT&CK
1 technique Privilege Escalation
References
https://access.redhat.com/errata/RHSA-2026:26562
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:26566
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:26590
access.redhat.com
and 34 more references View all →
News mentions
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