CVE-2021-3472

Se encontró un fallo en xorg-x11-server en versiones anteriores a 1.20.11. Se puede producir un subdesbordamiento de enteros en xserver que puede conllevar a una escalada de privilegios local. 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. An interger underflow can occur in xserver which can lead to a local privilege escalation. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

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 XChangeFeedbackControl requests. The issue results from the lack of proper validation of user-supplied data, which can result in an integer underflow before writing to memory. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of root.