CVE-2026-56000
Description
A flaw was found in the X.org X11 server, specifically within the GLX (OpenGL Extension to the X Window System) dispatch layer. A remote attacker can exploit this vulnerability by sending a series of crafted X11 requests. This can lead to a use-after-free condition, where the server attempts to write data to memory that has already been released. The primary consequence of this memory corruption is a denial of service, potentially causing the X server to crash.
Statement
An Important use-after-free vulnerability in the X.org X11 server's GLX dispatch layer allows a remote, unauthenticated attacker to trigger a denial of service. By sending a sequence of crafted X11 requests, an attacker can cause the X server to crash, impacting the availability of systems with a running graphical environment. This is considered Important due to the remote attack vector and the potential for unauthenticated denial of service.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.5 | 7.8 | N/A |
| Attack Vector | Network | Local | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | Low | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | High | N/A |
| Integrity Impact | None | High | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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