CVE-2026-56000
CWE-416Published: July 8, 2026· Updated: Jul 9, 2026
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.
Risk Analysis
This critical vulnerability allows local attackers with an X connection to cause a Heap Use After Free in xorg-server and xwayland. The high CVSS score of 9.0 indicates a severe impact on confidentiality, integrity, and availability, making it an urgent concern for affected systems.
No public exploit is currently known for this vulnerability. However, its remote exploitability (AV:N) and low attack complexity suggest that if an exploit were developed, it could be easily leveraged.
To mitigate this vulnerability, users should upgrade xorg-server to version 21.2.24 or later and xwayland to version 24.1.13 or later.
Technical Analysis
CVE-2026-56000 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 7.8.
From a weakness classification perspective (CWE-416): Use-after-free vulnerabilities involve accessing memory after it has been freed, often enabling arbitrary code execution.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (2)
Quick Facts
Related CVEs (CWE-416)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-56000 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts