Vulnerability · Published Feb 25, 2025 · Assigned by redhat

CVE-2025-26596Xorg: xwayland: heap overflow in xkbwritekeysyms()

High 7.8

In plain English

A high-severity out-of-bounds write in xserver. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 38% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.8High
Exploit odds (30 days)0.4%top 61.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:8tigervnc1.13.1-15.el8_10ALSA-2025:2502
AlmaLinux:9tigervnc1.14.1-1.el9_5.1ALSA-2025:2500
AlmaLinux:8tigervnc-icons1.13.1-15.el8_10ALSA-2025:2502
AlmaLinux:9tigervnc-icons1.14.1-1.el9_5.1ALSA-2025:2500
AlmaLinux:8tigervnc-license1.13.1-15.el8_10ALSA-2025:2502
AlmaLinux:9tigervnc-license1.14.1-1.el9_5.1ALSA-2025:2500
AlmaLinux:8tigervnc-selinux1.13.1-15.el8_10ALSA-2025:2502
AlmaLinux:9tigervnc-selinux1.14.1-1.el9_5.1ALSA-2025:2500
AlmaLinux:8tigervnc-server1.13.1-15.el8_10ALSA-2025:2502
AlmaLinux:9tigervnc-server1.14.1-1.el9_5.1ALSA-2025:2500
AlmaLinux:8tigervnc-server-minimal1.13.1-15.el8_10ALSA-2025:2502
AlmaLinux:9tigervnc-server-minimal1.14.1-1.el9_5.1ALSA-2025:2500
AlmaLinux:8tigervnc-server-module1.13.1-15.el8_10ALSA-2025:2502
AlmaLinux:9tigervnc-server-module1.14.1-1.el9_5.1ALSA-2025:2500
AlmaLinux:9xorg-x11-server-Xdmx1.20.11-28.el9_6ALSA-2025:7163
AlmaLinux:9xorg-x11-server-Xephyr1.20.11-28.el9_6ALSA-2025:7163
AlmaLinux:9xorg-x11-server-Xnest1.20.11-28.el9_6ALSA-2025:7163
AlmaLinux:9xorg-x11-server-Xorg1.20.11-28.el9_6ALSA-2025:7163
AlmaLinux:9xorg-x11-server-Xvfb1.20.11-28.el9_6ALSA-2025:7163
AlmaLinux:9xorg-x11-server-Xwayland23.2.7-3.el9_6ALSA-2025:7165
AlmaLinux:9xorg-x11-server-Xwayland-devel23.2.7-3.el9_6ALSA-2025:7165
AlmaLinux:9xorg-x11-server-common1.20.11-28.el9_6ALSA-2025:7163
AlmaLinux:9xorg-x11-server-devel1.20.11-28.el9_6ALSA-2025:7163
AlmaLinux:9xorg-x11-server-source1.20.11-28.el9_6ALSA-2025:7163
Debian:12xorg-server2:21.1.7-3+deb12u9DEBIAN-CVE-2025-26596
Debian:12xorg-server2:21.1.7-3+deb12u9DSA-5872-1
Debian:13xorg-server2:21.1.16-1DEBIAN-CVE-2025-26596
Debian:14xorg-server2:21.1.16-1DEBIAN-CVE-2025-26596
Debian:12xwaylandno fix listedDEBIAN-CVE-2025-26596
Debian:13xwayland2:24.1.6-1DEBIAN-CVE-2025-26596
Debian:14xwayland2:24.1.6-1DEBIAN-CVE-2025-26596
Rocky Linux:8tigervnc0:1.13.1-15.el8_10RLSA-2025:2502
Rocky Linux:9tigervnc0:1.14.1-1.el9_5.1RLSA-2025:2500
Rocky Linux:9xorg-x11-server0:1.20.11-28.el9_6RLSA-2025:7163
Rocky Linux:10xorg-x11-server-Xwayland0:24.1.5-3.el10_0RLSA-2025:7458
Rocky Linux:9xorg-x11-server-Xwayland0:23.2.7-3.el9_6RLSA-2025:7165
Ubuntu:22.04:LTSxorg-server2:21.1.4-2ubuntu1.7~22.04.13UBUNTU-CVE-2025-26596
Ubuntu:22.04:LTSxorg-server2:21.1.4-2ubuntu1.7~22.04.13USN-7299-1
Ubuntu:24.04:LTSxorg-server2:21.1.12-1ubuntu1.2USN-7299-1
Ubuntu:24.04:LTSxorg-server2:21.1.12-1ubuntu1.2UBUNTU-CVE-2025-26596
Ubuntu:25.10xorg-server2:21.1.16-1ubuntu1UBUNTU-CVE-2025-26596
Ubuntu:22.04:LTSxwayland2:22.1.1-1ubuntu0.17UBUNTU-CVE-2025-26596
Ubuntu:22.04:LTSxwayland2:22.1.1-1ubuntu0.17USN-7299-1
Ubuntu:24.04:LTSxwayland2:23.2.6-1ubuntu0.4UBUNTU-CVE-2025-26596
Ubuntu:24.04:LTSxwayland2:23.2.6-1ubuntu0.4USN-7299-1

Affected products (as reported)

VendorProductVersions
xserver 0 – before 21.1.1622.0.0 – before 24.1.6
Red Hat Red Hat Enterprise Linux 10 see references
Red Hat Red Hat Enterprise Linux 6 Extended Lifecycle Support - EXTENSION see references
Red Hat Red Hat Enterprise Linux 7 Extended Lifecycle Support see references
Red Hat Red Hat Enterprise Linux 7 Extended Lifecycle Support see references
Red Hat Red Hat Enterprise Linux 8 see references
Red Hat Red Hat Enterprise Linux 8.2 Advanced Update Support see references
Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support see references
Red Hat Red Hat Enterprise Linux 8.4 Telecommunications Update Service see references
Red Hat Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions see references
Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support see references
Red Hat Red Hat Enterprise Linux 8.6 Telecommunications Update Service see references
Red Hat Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions see references
Red Hat Red Hat Enterprise Linux 8.8 Extended Update Support see references
Red Hat Red Hat Enterprise Linux 9 see references
Red Hat Red Hat Enterprise Linux 9 see references
Red Hat Red Hat Enterprise Linux 9 see references
Red Hat Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions see references
Red Hat Red Hat Enterprise Linux 9.2 Extended Update Support see references
Red Hat Red Hat Enterprise Linux 9.4 Extended Update Support see references
Red Hat Red Hat Enterprise Linux 6 see references
Red Hat Red Hat Enterprise Linux 8 see references
Red Hat Red Hat Enterprise Linux 8 see references

Weakness: CWE-787 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References