An out-of-bounds memory access vulnerability exists in the X.Org server that can be triggered when a device frozen by a sync grab is reattached to a different master device. This flaw may cause application crashes, local privilege escalation if the server runs with extended privileges, or remote code execution in SSH X11 forwarding environments. Red Hat Enterprise Linux 8 and 9 ship X.Org server without root privileges, reducing the severity to moderate for those distributions. No effective mitigation is currently available according to Red Hat.