high
7.8
CWE
119
Advisory Published
CVE Published
Advisory Published
Updated

CVE-2021-4009: X.Org Server SProcXFixesCreatePointerBarrier Out-Of-Bounds Access Local Privilege Escalation Vulnerability

First published: Tue 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 SProcXFixesCreatePointerBarrier function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Credit: secalert@redhat.com secalert@redhat.com secalert@redhat.com

Affected SoftwareAffected VersionHow to fix
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=9.0
Debian Debian Linux=10.0
Debian Debian Linux=11.0
X.Org Server
ubuntu/xorg-server<2:1.19.6-1ubuntu4.10
2:1.19.6-1ubuntu4.10
ubuntu/xorg-server<2:1.20.13-1ubuntu1~20.04.2
2:1.20.13-1ubuntu1~20.04.2
ubuntu/xorg-server<2:1.20.13-1ubuntu2
2:1.20.13-1ubuntu2
ubuntu/xorg-server<2:1.20.13-1ubuntu2
2:1.20.13-1ubuntu2
ubuntu/xorg-server<2:1.15.1-0ubuntu2.11+
2:1.15.1-0ubuntu2.11+
ubuntu/xorg-server<21.1.2
21.1.2
ubuntu/xorg-server<2:1.18.4-0ubuntu0.12+
2:1.18.4-0ubuntu0.12+
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-16.04<2:1.19.6-1ubuntu4.1~16.04.6+
2:1.19.6-1ubuntu4.1~16.04.6+
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<2:21.1.2-0ubuntu1.1
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<2:21.1.1-0ubuntu1.1
2:21.1.1-0ubuntu1.1
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+deb10u4
2:1.20.4-1+deb10u13
2:1.20.11-1+deb11u11
2:21.1.7-3+deb12u5
2:21.1.11-2
debian/xwayland
2:22.1.9-1
2:23.2.4-1
<1.20.14
=21.1.0
=21.1.1
=34
=35
=9.0
=10.0
=11.0

Remedy

https://gitlab.freedesktop.org/xorg/xserver/-/commit/b5196750099ae6ae582e1f46bd0a6dad29550e02

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the vulnerability ID for this vulnerability?

    The vulnerability ID for this vulnerability is CVE-2021-4009.

  • What is the severity of CVE-2021-4009?

    The severity of CVE-2021-4009 is high with a severity value of 7.8.

  • How does CVE-2021-4009 affect X.Org Server?

    CVE-2021-4009 allows local attackers to escalate privileges on affected installations of X.Org Server.

  • How can CVE-2021-4009 be exploited?

    An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit CVE-2021-4009.

  • What is the remedy for CVE-2021-4009?

    The recommended remedy for CVE-2021-4009 depends on the version of X.Org Server being used, please refer to the official sources for specific remediation steps.

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