Description
A flaw was found in the X.Org X server. This vulnerability, an out-of-bounds read, affects the XKB (X Keyboard Extension) modifier map handling. An attacker with access to the X11 server can exploit this by sending a malformed request, which causes the server to read beyond its intended memory boundaries. This can lead to the exposure of sensitive information or cause the server to crash, resulting in a denial of service.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 6 Extended Lifecycle Support - EXTENSION | — | — |
| Red Hat | Red Hat Enterprise Linux 7 Extended Lifecycle Support | — | — |
| Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | — | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | — | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Telecommunications Update Service | — | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | — | — |
| Red Hat | Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Extended Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 6 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | xorg-server | 2:21.1.22-1 | — |
| Debian 14 | xwayland | 2:24.1.10-1 | — |
| Debian 13 | xorg-server | 2:21.1.16-1.3+deb13u2 | — |
| Debian 13 | xwayland | No fix yet | — |
| Debian 12 | xorg-server | 2:21.1.7-3+deb12u12 | — |
| Debian 12 | xwayland | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | xwayland +1 | No fix yet | — |
| Ubuntu 25.10 | xwayland +1 | No fix yet | — |
| Ubuntu 24.04 LTS | xwayland +1 | No fix yet | — |
| Ubuntu 22.04 LTS | xwayland +1 | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | xorg-server | No fix yet | — |
| Ubuntu Pro 18.04 LTS | xorg-server +1 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | xorg-server +1 | No fix yet | — |
| Ubuntu Pro 14.04 LTS | xorg-server | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10.0 EUS | xorg-x11-server-Xwayland +1 | 24.1.5-6.el10_0 | RHSA-2026:20563 |
| RHEL 9.6 EUS | tigervnc +6 | 1.14.1-10.el9_6 | RHSA-2026:22424 |
| RHEL 9.6 EUS | xorg-x11-server +8 | 1.20.11-33.el9_6 | RHSA-2026:20558 |
| RHEL 9.6 EUS | xorg-x11-server-Xwayland +1 | 23.2.7-6.el9_6 | RHSA-2026:20561 |
| RHEL 9.4 EUS | tigervnc +6 | 1.13.1-8.el9_4.9 | RHSA-2026:20575 |
| RHEL 9.4 EUS | xorg-x11-server +8 | 1.20.11-28.el9_4 | RHSA-2026:20555 |
| RHEL 9.4 EUS | xorg-x11-server-Xwayland | 22.1.9-8.el9_4 | RHSA-2026:20560 |
Show 12 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9.2 E4S | tigervnc +6 | 1.12.0-14.el9_2.14 | RHSA-2026:20576 |
| RHEL 9.2 E4S | xorg-x11-server +6 | 1.20.11-20.el9_2 | RHSA-2026:20557 |
| RHEL 9.2 E4S | xorg-x11-server-Xwayland | 21.1.3-10.el9_2 | RHSA-2026:20547 |
| RHEL 9.0 E4S | tigervnc +6 | 1.11.0-22.el9_0.17 | RHSA-2026:21741 |
| RHEL 9.0 E4S | xorg-x11-server +6 | 1.20.11-13.el9_0 | RHSA-2026:21699 |
| RHEL 9.0 E4S | xorg-x11-server-Xwayland | 21.1.3-5.el9_0 | RHSA-2026:20562 |
| RHEL 8.8 TUS | tigervnc +6 | 1.12.0-15.el8_8.17 | RHSA-2026:23255 |
| RHEL 8.8 TUS | xorg-x11-server +6 | 1.20.11-18.el8_8 | RHSA-2026:21742 |
| RHEL 8.8 TUS | xorg-x11-server-Xwayland | 21.1.3-13.el8_8 | RHSA-2026:21712 |
| RHEL 8.8 E4S | tigervnc +6 | 1.12.0-15.el8_8.17 | RHSA-2026:23255 |
| RHEL 8.8 E4S | xorg-x11-server +6 | 1.20.11-18.el8_8 | RHSA-2026:21742 |
| RHEL 8.8 E4S | xorg-x11-server-Xwayland | 21.1.3-13.el8_8 | RHSA-2026:21712 |
| RHEL 8.6 TUS | xorg-x11-server +6 | 1.20.11-7.el8_6 | RHSA-2026:21718 |
| RHEL 8.6 TUS | xorg-x11-server-Xwayland | 21.1.3-2.el8_6.6 | RHSA-2026:21716 |
| RHEL 8.6 EUS Long Life | tigervnc +6 | 1.12.0-6.el8_6.17 | RHSA-2026:24341 |
| RHEL 8.6 E4S | xorg-x11-server +6 | 1.20.11-7.el8_6 | RHSA-2026:21718 |
| RHEL 8.6 E4S | xorg-x11-server-Xwayland | 21.1.3-2.el8_6.6 | RHSA-2026:21716 |
| RHEL 8.6 AUS | tigervnc +6 | 1.12.0-6.el8_6.17 | RHSA-2026:24341 |
| RHEL 8.6 AUS | xorg-x11-server +6 | 1.20.11-7.el8_6 | RHSA-2026:21718 |
| RHEL 8.6 AUS | xorg-x11-server-Xwayland | 21.1.3-2.el8_6.6 | RHSA-2026:21716 |
| RHEL 8.4 EUS Long Life | tigervnc +6 | 1.11.0-8.el8_4.15 | RHSA-2026:23254 |
| RHEL 8.4 EUS Long Life | xorg-x11-server +7 | 1.20.10-4.el8_4 | RHSA-2026:21715 |
| RHEL 8.4 AUS | tigervnc +6 | 1.11.0-8.el8_4.15 | RHSA-2026:23254 |
| RHEL 8.4 AUS | xorg-x11-server +7 | 1.20.10-4.el8_4 | RHSA-2026:21715 |
| RHEL 7 ELS | tigervnc +6 | 1.8.0-36.el7_9.4 | RHSA-2026:22456 |
| RHEL 7 ELS | xorg-x11-server +9 | 1.20.4-34.el7_9 | RHSA-2026:20590 |
| RHEL 6 ELS | tigervnc +3 | 1.1.0-25.el6_10.16 | RHSA-2026:23496 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | xorg-x11-server | 21.1.15-150700.5.16.1 | SUSE-SU-2026:1330-1 |
| SLES 15 SP7 | xwayland | 24.1.5-150700.3.14.1 | SUSE-SU-2026:1328-1 |
| SLES 15 SP6 | xorg-x11-server | 21.1.11-150600.5.25.1 | SUSE-SU-2026:1331-1 |
| SLES 15 SP5 | xorg-x11-server | 21.1.4-150500.7.46.1 | SUSE-SU-2026:1335-1 |
| SLES 15 SP4 | xorg-x11-server | 1.20.3-150400.38.68.1 | SUSE-SU-2026:1333-1 |
| SLES 12 SP5 | xorg-x11-server | 1.19.6-10.99.1 | SUSE-SU-2026:1332-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | xwayland | 24.1.6-160000.4.1 | SUSE-SU-2026:21211-1 |
| SLES for SAP 15 SP6 | xorg-x11-server | 21.1.11-150600.5.25.1 | SUSE-SU-2026:1331-1 |
| SLES for SAP 15 SP5 | xorg-x11-server | 21.1.4-150500.7.46.1 | SUSE-SU-2026:1335-1 |
| SLES for SAP 15 SP4 | xorg-x11-server | 1.20.3-150400.38.68.1 | SUSE-SU-2026:1333-1 |
| SLES 16.0 | xwayland | 24.1.6-160000.4.1 | SUSE-SU-2026:21211-1 |
| SLE HPC 15 SP5 | xorg-x11-server | 21.1.4-150500.7.46.1 | SUSE-SU-2026:1335-1 |
| SLE HPC 15 SP4 | xorg-x11-server | 1.20.3-150400.38.68.1 | SUSE-SU-2026:1333-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | xorg-x11-server | 21.1.21-5.1 | openSUSE-SU-2026:10556-1 |
| openSUSE Tumbleweed | xwayland | 24.1.9-2.1 | openSUSE-SU-2026:10557-1 |
| openSUSE Leap 16.0 | xorg-x11-server | 21.1.15-160000.4.1 | openSUSE-SU-2026:20544-1 |
| openSUSE Leap 16.0 | xwayland | 24.1.6-160000.4.1 | openSUSE-SU-2026:20560-1 |
| openSUSE Leap 15.6 | xorg-x11-server | 21.1.11-150600.5.25.1 | SUSE-SU-2026:1331-1 |
| openSUSE Leap 15.6 | xwayland | 24.1.1-150600.5.23.1 | SUSE-SU-2026:1329-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | xorg-server | 21.1.22-r0 | — |
| Alpine v3.24 | xwayland | 24.1.10-r0 | — |
| Alpine v3.23 | xorg-server | 21.1.22-r0 | — |
| Alpine v3.23 | xwayland | 24.1.10-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | tigervnc +6 | 1.14.1-3.amzn2023.0.5 | ALAS2023-2026-1626 |
| Amazon Linux 2023 | xorg-x11-server-Xorg +6 | 21.1.13-5.amzn2023.0.9 | ALAS2023-2026-1614 |
| Amazon Linux 2023 | xorg-x11-server-Xwayland +1 | 24.1.3-1.amzn2023.0.4 | ALAS2023-2026-1613 |
| Amazon Linux 2 | tigervnc +6 | 1.8.0-24.amzn2.0.9 | ALAS2-2026-3273 |
| Amazon Linux 2 | xorg-x11-server-Xdmx +8 | 1.20.4-22.amzn2.0.11 | ALAS2-2026-3268 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | xorg-x11-server | No fix yet | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | tigervnc +6 | 1.8.0-33.0.11.el7_9 | ELSA-2026-22456 |
| Oracle Linux 7 | xorg-x11-server-Xdmx +8 | 1.20.4-29.0.7.el7_9 | ELSA-2026-20590 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | xorg-server | 21.1.22-r0 | — |
Advisories 45
- WID-SEC-2026-2455 Oracle Solaris Drittanbieterkomponenten: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- RHSA-2026:24341 Red Hat Security Advisory: tigervnc security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:23496 Red Hat Security Advisory: tigervnc security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:23255 Red Hat Security Advisory: tigervnc security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:23254 Red Hat Security Advisory: tigervnc security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:22456 Red Hat Security Advisory: tigervnc security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:22424 Red Hat Security Advisory: tigervnc security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:21741 Red Hat Security Advisory: tigervnc security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:21742 Red Hat Security Advisory: xorg-x11-server security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:21716 Red Hat Security Advisory: xorg-x11-server-Xwayland security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:21718 Red Hat Security Advisory: xorg-x11-server security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:21715 Red Hat Security Advisory: xorg-x11-server security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:21712 Red Hat Security Advisory: xorg-x11-server-Xwayland security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:21699 Red Hat Security Advisory: xorg-x11-server security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:20590 Red Hat Security Advisory: xorg-x11-server security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:20575 Red Hat Security Advisory: tigervnc security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:20576 Red Hat Security Advisory: tigervnc security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:20562 Red Hat Security Advisory: xorg-x11-server-Xwayland security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:20563 Red Hat Security Advisory: xorg-x11-server-Xwayland security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:20561 Red Hat Security Advisory: xorg-x11-server-Xwayland security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:20558 Red Hat Security Advisory: xorg-x11-server security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:20560 Red Hat Security Advisory: xorg-x11-server-Xwayland security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:20557 Red Hat Security Advisory: xorg-x11-server security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:20555 Red Hat Security Advisory: xorg-x11-server security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:20547 Red Hat Security Advisory: xorg-x11-server-Xwayland security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- WID-SEC-2026-1119 X.Org X11, Xwayland: Mehrere Schwachstellen BSI CERT-Bund (WID) · Aug 25, 2026
- ELSA-2026-22456 Important: tigervnc security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Jul 9, 2026
- ELSA-2026-20590 Important: xorg-x11-server security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Jul 8, 2026
- ALAS2023-2026-1614 Important: xorg-x11-server security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Apr 30, 2026
- ALAS2023-2026-1626 Important: tigervnc security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Apr 30, 2026
- ALAS2023-2026-1613 Important: xorg-x11-server-Xwayland security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Apr 30, 2026
- ALAS2-2026-3268 Important: xorg-x11-server security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Apr 29, 2026
- ALAS2-2026-3273 Important: tigervnc security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Apr 29, 2026
- openSUSE-SU-2026:20560-1 Security update for xwayland SUSE / openSUSE Security Updates · Apr 22, 2026
- openSUSE-SU-2026:20544-1 Security update for xorg-x11-server SUSE / openSUSE Security Updates · Apr 22, 2026
- SUSE-SU-2026:21211-1 Security update for xwayland SUSE / openSUSE Security Updates · Apr 22, 2026
- openSUSE-SU-2026:10556-1 xorg-x11-server-21.1.21-5.1 on GA media SUSE / openSUSE Security Updates · Apr 16, 2026
- openSUSE-SU-2026:10557-1 xwayland-24.1.9-2.1 on GA media SUSE / openSUSE Security Updates · Apr 16, 2026
- SUSE-SU-2026:1332-1 Security update for xorg-x11-server SUSE / openSUSE Security Updates · Apr 16, 2026
- SUSE-SU-2026:1333-1 Security update for xorg-x11-server SUSE / openSUSE Security Updates · Apr 16, 2026
- SUSE-SU-2026:1330-1 Security update for xorg-x11-server SUSE / openSUSE Security Updates · Apr 16, 2026
- SUSE-SU-2026:1329-1 Security update for xwayland SUSE / openSUSE Security Updates · Apr 16, 2026
- SUSE-SU-2026:1331-1 Security update for xorg-x11-server SUSE / openSUSE Security Updates · Apr 16, 2026
- SUSE-SU-2026:1328-1 Security update for xwayland SUSE / openSUSE Security Updates · Apr 16, 2026
- SUSE-SU-2026:1335-1 Security update for xorg-x11-server SUSE / openSUSE Security Updates · Apr 16, 2026
References
- RHSA-2026:20547 vendor-advisory
- RHSA-2026:20555 vendor-advisory
- RHSA-2026:20557 vendor-advisory
- RHSA-2026:20558 vendor-advisory
- RHSA-2026:20560 vendor-advisory
- RHSA-2026:20561 vendor-advisory
- RHSA-2026:20562 vendor-advisory
- RHSA-2026:20563 vendor-advisory
- RHSA-2026:20575 vendor-advisory
- RHSA-2026:20576 vendor-advisory
- RHSA-2026:20590 vendor-advisory
- RHSA-2026:21699 vendor-advisory
- RHSA-2026:21712 vendor-advisory
- RHSA-2026:21715 vendor-advisory
- RHSA-2026:21716 vendor-advisory
- RHSA-2026:21718 vendor-advisory
- RHSA-2026:21741 vendor-advisory
- RHSA-2026:21742 vendor-advisory
- RHSA-2026:22424 vendor-advisory
- RHSA-2026:22456 vendor-advisory
- RHSA-2026:23254 vendor-advisory
- RHSA-2026:23255 vendor-advisory
- RHSA-2026:23496 vendor-advisory
- RHSA-2026:24341 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-34002 vdb-entry
- RHBZ#2451112 issue-tracking