CVE-2022-46340

Se encontró una vulnerabilidad en X.Org. Esta falla de seguridad se produce porque el controlador de intercambio para la solicitud XTestFakeInput de la extensión XTest puede dañar la pila si se envían GenericEvents con longitudes superiores a 32 bytes a través de una solicitud XTestFakeInput. Este problema puede provocar una elevación de privilegios locales en sistemas donde el servidor X ejecuta código privilegiado y remoto para sesiones de reenvío ssh X. Este problema no afecta a los sistemas donde el cliente y el servidor utilizan el mismo orden de bytes.

A vulnerability was found in X.Org. The issue occurs due to the swap handler for the XTestFakeInput request of the XTest extension, possibly corrupting the stack if GenericEvents with lengths larger than 32 bytes are sent through the XTestFakeInput request. This flaw can lead to local privilege elevation on systems where the X server runs privileged and remote code execution for ssh X forwarding sessions. This issue does not affect systems where the client and server use the same byte order.

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 handling of XTestFakeInput requests. The issue results from the lack of proper validation of user-supplied data, which can result in a type confusion condition. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of root.