A flaw was found in the X.Org X server. This use-after-free vulnerability occurs in the XSYNC fence triggering logic, specifically within the miSyncTriggerFence() function. An attacker with access to the X11 server can exploit this without user interaction, leading to a server crash and potentially enabling memory corruption. This could result in a denial of service or further compromise of the system.
To mitigate this issue, restrict access to the X11 server to trusted users and networks. If the X.Org X server is not required, consider disabling or uninstalling it. For environments where the X server is essential, running X applications within a sandboxed environment can help reduce the attack surface.