CVE-2026-50257

Published: Giu 05, 2026 Last Modified: Giu 05, 2026

ExploitDB:

Other exploit source:

Google Dorks:

HIGH 7,8

Source: [email protected]

Attack Vector: local

Attack Complexity: low

Privileges Required: low

User Interaction: none

Scope: unchanged

Confidentiality: high

Integrity: high

Availability: high

Description

AI Translation Available

A use-after-free flaw was found in the X.Org X server and Xwayland in miSyncDestroyFence(). A client that sets up multiple fence triggers can trigger a use-after-free function pointer call. An attacker would connect to the X server to set up a fence and await that fence, then a second X connection destroys the fence, causing the use-after-free. This may be used to crash the server, or for privilege escalation if the X server runs as root.