ZDI-21-1550: X.Org Server SwapCreateRegister 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 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.

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-21-1550?

ZDI-21-1550 has a severity rating that indicates it allows local privilege escalation.

2

How do I fix ZDI-21-1550?

To fix ZDI-21-1550, update the X.Org Server to the latest patched version provided by the vendor.

3

Who is affected by ZDI-21-1550?

ZDI-21-1550 affects installations of the X.Org Server that are running vulnerable versions.

4

What type of vulnerability is ZDI-21-1550?

ZDI-21-1550 is classified as a local privilege escalation vulnerability.

5

What is required to exploit ZDI-21-1550?

Exploitation of ZDI-21-1550 requires the attacker to have the ability to execute low-privileged code on the target system.

Contact

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