CVE-2021-4010: X.Org Server SProcScreenSaverSuspend Out-Of-Bounds Access Local Privilege Escalation Vulnerability

Published Dec 14, 2021
·
Updated

A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14. An out-of-bounds access can occur in the SProcScreenSaverSuspend function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Other sources

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.

ZDI

Affected Software

24 affected componentsFixes available
ubuntu/xorg-server<2:1.20.13-1ubuntu2
2:1.20.13-1ubuntu2
ubuntu/xorg-server<2:1.20.13-1ubuntu2
2:1.20.13-1ubuntu2
ubuntu/xorg-server<21.1.2
21.1.2
ubuntu/xorg-server<2:1.20.13-1ubuntu1~20.04.2
2:1.20.13-1ubuntu1~20.04.2
ubuntu/xorg-server<2:1.20.11-1ubuntu1.2
2:1.20.11-1ubuntu1.2
ubuntu/xorg-server<2:1.20.13-1ubuntu1.1
2:1.20.13-1ubuntu1.1
ubuntu/xorg-server<2:1.20.13-1ubuntu2
2:1.20.13-1ubuntu2
ubuntu/xorg-server-hwe-18.04<2:1.20.8-2ubuntu2.2~18.04.6
2:1.20.8-2ubuntu2.2~18.04.6
ubuntu/xwayland<2:21.1.1-0ubuntu1.1
2:21.1.1-0ubuntu1.1
ubuntu/xwayland<2:21.1.2-0ubuntu1.1
2:21.1.2-0ubuntu1.1
ubuntu/xwayland<2:21.1.3-1ubuntu1
2:21.1.3-1ubuntu1
ubuntu/xwayland<2:21.1.3-1ubuntu1
2:21.1.3-1ubuntu1
ubuntu/xwayland<21.1.4
21.1.4
ubuntu/xwayland<2:21.1.3-1ubuntu1
2:21.1.3-1ubuntu1
debian/xorg-server
2:1.20.4-1+deb10u42:1.20.4-1+deb10u132:1.20.11-1+deb11u112:21.1.7-3+deb12u52:21.1.11-2
debian/xwayland
2:22.1.9-12:23.2.4-1
X.Org Server
X.Org X Server<1.20.14
X.Org X Server=21.1.0
X.Org X Server=21.1.1
Fedoraproject Fedora=34
Fedoraproject Fedora=35
Debian Debian Linux=10.0
Debian Debian Linux=11.0

Event History

Dec 14, 2021
CVE Published
via Ubuntu·12:00 AM
Dec 17, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionWeakness
Jan 12, 2024
Data Sourced
via Launchpad·12:00 AM
Description
Feb 26, 2025
Advisory Published
via ZDI·07:39 PM

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2021-4010?

CVE-2021-4010 is a vulnerability in X.Org Server that allows local attackers to escalate privileges.

2

How can this vulnerability be exploited?

To exploit CVE-2021-4010, an attacker must first execute low-privileged code on the target system.

3

Is there a specific version of X.Org Server affected by this vulnerability?

Yes, X.Org Server 2:1.20.13-1ubuntu2 and earlier versions are affected by CVE-2021-4010.

4

How can I fix this vulnerability in X.Org Server?

To fix CVE-2021-4010, update X.Org Server to version 2:1.20.13-1ubuntu2 or apply the recommended security patches.

5

What is the severity of CVE-2021-4010?

CVE-2021-4010 has a severity rating of 7.8 (High).

Contact

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