X.Org Server Xkb Key Types 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 the num_levels field. 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/543e108516428fc8c3bea91d6563ad266f9a801e
Disclosure Timeline
- 2026-04-17 - Vulnerability reported to vendor
- 2026-06-24 - Coordinated public release of advisory
- 2026-06-24 - Advisory Updated
Credit
Anonymous
