Vulnerability · Published Jul 8, 2026 · Assigned by suse
CVE-2026-56000xorg-x11-server / xwayland GLX contextTags Use-After-Free in CommonMakeCurrent()
Critical 9.0
In plain English
A critical-severity use-after-free in xorg-x11-server from X.Org. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 24% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 4.0)9.0Critical
Exploit odds (30 days)0.3%top 76.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Local attackers with a X connection able to provide GLX commit to the X server xorg-server before 21.2.24 and xwayland before 24.1.13 could cause a Heap Use After Free, due to CommonMakeCurrent() pointing into potentially reallocated memory.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:10 | xorg-x11-server-Xwayland | 24.1.9-4.el10_2.3 | ALSA-2026:38489 |
| AlmaLinux:9 | xorg-x11-server-Xwayland | 24.1.9-4.el9_8.3 | ALSA-2026:38490 |
| AlmaLinux:10 | xorg-x11-server-Xwayland-devel | 24.1.9-4.el10_2.3 | ALSA-2026:38489 |
| AlmaLinux:9 | xorg-x11-server-Xwayland-devel | 24.1.9-4.el9_8.3 | ALSA-2026:38490 |
| Alpine:v3.24 | xorg-server | 21.1.24-r0 | ALPINE-CVE-2026-56000 |
| Alpine:v3.24 | xwayland | 24.1.13-r0 | ALPINE-CVE-2026-56000 |
| Debian:12 | xorg-server | no fix listed | DEBIAN-CVE-2026-56000 |
| Debian:13 | xorg-server | 2:21.1.16-1.3+deb13u4 | DEBIAN-CVE-2026-56000 |
| Debian:14 | xorg-server | 2:21.1.24-1 | DEBIAN-CVE-2026-56000 |
| Debian:12 | xwayland | no fix listed | DEBIAN-CVE-2026-56000 |
| Debian:13 | xwayland | no fix listed | DEBIAN-CVE-2026-56000 |
| Debian:14 | xwayland | 2:24.1.13-1 | DEBIAN-CVE-2026-56000 |
| Rocky Linux:10 | xorg-x11-server-Xwayland | 0:24.1.9-4.el10_2.3 | RLSA-2026:38489 |
| Rocky Linux:9 | xorg-x11-server-Xwayland | 0:24.1.9-4.el9_8.3 | RLSA-2026:38490 |
| Ubuntu:22.04:LTS | xorg-server | no fix listed | UBUNTU-CVE-2026-56000 |
| Ubuntu:24.04:LTS | xorg-server | no fix listed | UBUNTU-CVE-2026-56000 |
| Ubuntu:25.10 | xorg-server | no fix listed | UBUNTU-CVE-2026-56000 |
| Ubuntu:26.04:LTS | xorg-server | no fix listed | UBUNTU-CVE-2026-56000 |
| Ubuntu:26.10 | xorg-server | no fix listed | UBUNTU-CVE-2026-56000 |
| Ubuntu:22.04:LTS | xwayland | no fix listed | UBUNTU-CVE-2026-56000 |
| Ubuntu:24.04:LTS | xwayland | no fix listed | UBUNTU-CVE-2026-56000 |
| Ubuntu:25.10 | xwayland | no fix listed | UBUNTU-CVE-2026-56000 |
| Ubuntu:26.04:LTS | xwayland | no fix listed | UBUNTU-CVE-2026-56000 |
| Ubuntu:26.10 | xwayland | no fix listed | UBUNTU-CVE-2026-56000 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| X.Org | xorg-x11-server | 0 – before 21.1.24 |
| X.Org | xwayland | 0 – before 24.1.13 |
Weakness: CWE-416 · Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H