CVE-2021-4011

Se ha encontrado un fallo en xorg-x11-server en versiones anteriores a 21.1.2 y anteriores a 1.20.14. Puede producirse un acceso fuera de límites en la función SwapCreateRegister. La mayor amenaza de esta vulnerabilidad es la confidencialidad e integridad de los datos, así como la disponibilidad del sistema

A flaw was found in xorg-x11-server where an out-of-bounds access can occur in the SwapCreateRegister function.

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 SwapCreateRegister requests. The issue results from the lack of proper validation of user-supplied data, which can result in a memory access past the end of an allocated buffer. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of root.