CVE-2026-93524

X.Org Server XKB SetMap Key Width/Action Count Desync Out-Of-Bounds Read

Published Oct 28, 2026 CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed
Description
A buffer overread in CheckKeySyms() in X.Org X Server before 21.1.25 and XWayland before 24.1.14 could be used by authenticated X clients to leak small amounts of information from X server memory or potentially crash the X server.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description A flaw was found in xorg-x11-server. An authenticated local user can trigger an out-of-bounds heap memory read by sending specially crafted X Keyboard Extension (XKB) requests with inconsistent key range parameters. This flaw leads to information disclosure, allowing the user to read sensitive data from the server's heap memory. A buffer overread in CheckKeySyms() in X.Org X Server before 21.1.25 and XWayland before 24.1.14 could be used by authenticated X clients to leak small amounts of information from X server memory or potentially crash the X server.
Title xorg-x11-server: XKB SetMap Key Width/Action Count Desync Out-Of-Bounds Read X.Org Server XKB SetMap Key Width/Action Count Desync Out-Of-Bounds Read
First Time appeared X.org xorg-x11-server
X.org xwayland
Weaknesses CWE-126
CPEs cpe:2.3:a:x.org:xorg-x11-server:*:*:*:*:*:*:*:*
cpe:2.3:a:x.org:xwayland:*:*:*:*:*:*:*:*
Vendors & Products X.org xorg-x11-server
X.org xwayland
References
Metrics cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N'}

Type Values Removed Values Added
First Time appeared X.org
X.org x Server
Vendors & Products X.org
X.org x Server
Type Values Removed Values Added
Description A flaw was found in xorg-x11-server. An authenticated local user can trigger an out-of-bounds heap memory read by sending specially crafted X Keyboard Extension (XKB) requests with inconsistent key range parameters. This flaw leads to information disclosure, allowing the user to read sensitive data from the server's heap memory.
Title xorg-x11-server: XKB SetMap Key Width/Action Count Desync Out-Of-Bounds Read
Weaknesses CWE-125
References
Metrics threat_severity

None

cvssV3_1

{'score': 3.3, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N'}

threat_severity

Low

Weaknesses

Sources

Status
PUBLISHED
Assigner
suse
Published
Updated
Nov 6, 2026, 6:32 PM
Reserved
Sep 18, 2026, 8:46 AM
Status
Awaiting Analysis
Published
Oct 28, 2026, 5:18 PM
Modified
Nov 6, 2026, 7:18 PM
Severity
Low
Public date
Oct 7, 2026, 12:00 PM