X.Org Server Font Alias Stack-based Buffer Overflow Privilege Escalation Vulnerability
Vulnerability Details
This vulnerability allows local attackers to escalate privileges on affected installations of X.Org Server. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability.
The specific flaw exists within font alias resolution. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of root.
Additional Details
X.Org has issued an update to correct this vulnerability. More details can be found at:
https://gitlab.freedesktop.org/xorg/xserver/-/commit/bb5158f962dc935e58ef8b4b5fcb31be201a6e07
Disclosure Timeline
- 2026-04-17 - Vulnerability reported to vendor
- 2026-06-24 - Coordinated public release of advisory
- 2026-06-24 - Advisory Updated
Credit
Anonymous
