CVE-2021-3472: X.Org Server XChangeFeedbackControl Integer Underflow Privilege Escalation Vulnerability

Published Mar 29, 2021
·
Updated

A flaw was found in xorg-x11-server in versions before 1.20.11. An integer 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.

Other sources

A vulnerability was found affecting X.Org-Server, where integer underflow exist in xserver, ProcXChangeFeedbackControl() leading to local privilege escalation

Red Hat

Affected Software

10 affected componentsFixes available
debian/xorg-server
2:1.20.4-1+deb10u42:1.20.4-1+deb10u92:1.20.11-1+deb11u62:21.1.7-32:21.1.8-1
redhat/xorg-x11-server<1.20.11
1.20.11
X.Org X Server<1.20.11
Fedoraproject Fedora=32
Fedoraproject Fedora=33
Fedoraproject Fedora=34
Debian Debian Linux=9.0
Debian Debian Linux=10.0
redhat Enterprise Linux=7.0
redhat Enterprise Linux=8.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/xorg-server to a version that resolves this vulnerability.

    Fixed in 2:1.20.4-1+deb10u4Fixed in 2:1.20.4-1+deb10u9Fixed in 2:1.20.11-1+deb11u6Fixed in 2:21.1.7-3Fixed in 2:21.1.8-1
  2. Upgrade

    Upgrade redhat/xorg-x11-server to a version that resolves this vulnerability.

    Fixed in 1.20.11
  3. Upgrade

    Upgrade xorg-x11-server to a version that resolves this vulnerability.

    Fixed in 1.20.11

Event History

Apr 26, 2021
CVE Published
via MITRE·02:29 PM
Data Sourced
via MITRE·02:29 PM
DescriptionWeakness
Data Sourced
via NVD·03:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Jun 29, 2026
Advisory Published
via ZDI·04:44 AM
Data Sourced
via ZDI·04:44 AM
DescriptionAffected Software

Frequently Asked Questions

1

What is CVE-2021-3472?

CVE-2021-3472 is a vulnerability in X.Org Server that allows local attackers to escalate privileges on affected installations.

2

How does CVE-2021-3472 impact X.Org Server?

CVE-2021-3472 allows local attackers to escalate privileges on affected installations of X.Org Server.

3

What is the severity of CVE-2021-3472?

CVE-2021-3472 has a severity rating of high.

4

How can CVE-2021-3472 be exploited?

To exploit CVE-2021-3472, an attacker must first obtain the ability to execute low-privileged code on the target system.

5

What is the remedy for CVE-2021-3472?

The remedy for CVE-2021-3472 is to update X.Org Server to versions 2:1.20.4-1+deb10u4, 2:1.20.4-1+deb10u9, 2:1.20.11-1+deb11u6, 2:21.1.7-3, or 2:21.1.8-1.

Contact

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