CVE-2025-26596

HIGH
MEDIUM Priority: 0.03 BB Relevance: 41/100
Published: 2025-02-25 Modified: 2026-11-04 First seen: 2026-11-04 Status: active

Attack Surface

Low Complexity No Interaction Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Local
AC: Low
PR: Low
UI: None
S: Unchanged
C: High
I: High
A: High

Description

A heap overflow flaw was found in X.Org and Xwayland. The computation of the length in XkbSizeKeySyms() differs from what is written in XkbWriteKeySyms(), which may lead to a heap-based buffer overflow.

Weakness Classification (1)

Affected Software (8)

VendorProductVersion
&mdash; &mdash; 0 < 21.1.16
&mdash; &mdash; 22.0.0 < 24.1.6
redhat enterprise_linux 7.0
redhat enterprise_linux 8.0
redhat enterprise_linux 9.0
tigervnc tigervnc -
x.org x_server < 21.1.16
x.org xwayland < 24.1.6

References & Advisories (18)

https://access.redhat.com/errata/RHSA-2025:2500
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:2502
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:2861
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:2862
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:2865
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:2866
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:2873
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:2874
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:2875
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:2879
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:2880
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:3976
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:7163
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:7165
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2025:7458
vendor-advisory x_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2345256
issue-tracking x_refsource_REDHAT

Bug Bounty Relevance

41 / 100
✓ Low complexity
✓ No user interaction

CVSS Score

7.8 / 10.0 v3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploitation Probability

0.44%
Raw Score 0.004380
Percentile 38.3%
Date 2026-11-09

EPSS Trend

2026-11-09
0.00438
2026-11-08
0.00438
2026-11-07
0.00438
2026-11-06
0.00438
2026-11-05
0.00438
2026-11-04
0.00438

Intelligence Sources

mitre ref →
nvd ref →