ZDI-21-1549: X.Org Server SProcScreenSaverSuspend Out-Of-Bounds Access Local Privilege Escalation Vulnerability

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 SProcScreenSaverSuspend 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.

Affected Software

1 affected component
X.Org Server

Event History

Feb 26, 2025
Advisory Published
via ZDI·07:39 PM

Frequently Asked Questions

1

What is the severity of ZDI-21-1549?

ZDI-21-1549 is classified as a high severity vulnerability.

2

How do I fix ZDI-21-1549?

To fix ZDI-21-1549, update your X.Org Server to the latest version that addresses this vulnerability.

3

Who is affected by ZDI-21-1549?

Organizations and systems running vulnerable versions of X.Org Server are affected by ZDI-21-1549.

4

What type of vulnerability is ZDI-21-1549?

ZDI-21-1549 is a local privilege escalation vulnerability.

5

Can ZDI-21-1549 be exploited remotely?

No, ZDI-21-1549 requires local access to the affected system to exploit the vulnerability.

Contact

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