CVE-2021-4011: X.Org Server SwapCreateRegister 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 SwapCreateRegister 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
| Affected Software | Affected Version | How 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 | <2:1.20.11-1ubuntu1.2 | 2:1.20.11-1ubuntu1.2 |
| ubuntu/xorg-server | <2:1.20.13-1ubuntu1.1 | 2:1.20.13-1ubuntu1.1 |
| ubuntu/xorg-server | <21.1.2 | 21.1.2 |
| ubuntu/xorg-server | <2:1.15.1-0ubuntu2.11+ | 2:1.15.1-0ubuntu2.11+ |
| ubuntu/xorg-server | <2:1.18.4-0ubuntu0.12+ | 2:1.18.4-0ubuntu0.12+ |
| 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 | <2:1.20.13-1ubuntu2 | 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 | <2:21.1.1-0ubuntu1.1 | 2:21.1.1-0ubuntu1.1 |
| ubuntu/xwayland | <2:21.1.2-0ubuntu1.1 | 2:21.1.2-0ubuntu1.1 |
| ubuntu/xwayland | <21.1.4 | 21.1.4 |
| 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 | <2:21.1.3-1ubuntu1 | 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+deb11u6 2:1.20.11-1+deb11u11 2:21.1.7-3+deb12u2 2:21.1.7-3+deb12u5 2:21.1.11-2 | |
| debian/xwayland | 2:22.1.9-1 2:23.2.4-1 |
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Reference Links
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PDHYZM6FII35JA7J275MFCJO6ADJUPQX/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/T57DCF726O5LLTST4NBL5PQ7DLPB46HT/
- https://lists.x.org/archives/xorg-announce/2021-December/003122.html
- https://lists.x.org/archives/xorg-announce/2021-December/003124.html
- https://www.debian.org/security/2021/dsa-5027
- https://www.zerodayinitiative.com/advisories/ZDI-21-1550/
- https://lists.debian.org/debian-lts-announce/2021/12/msg00035.html
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NKLSZCY47QK4RCJFXITYFALCGPJAFXOK/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NXTRPFEQLFZ6NT2LPLZEID664RGC3OCC/
- https://security.netapp.com/advisory/ntap-20220114-0004/
- https://security.gentoo.org/glsa/202305-30
- https://launchpad.net/bugs/cve/CVE-2021-4011
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NKLSZCY47QK4RCJFXITYFALCGPJAFXOK/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NXTRPFEQLFZ6NT2LPLZEID664RGC3OCC/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PDHYZM6FII35JA7J275MFCJO6ADJUPQX/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T57DCF726O5LLTST4NBL5PQ7DLPB46HT/
- https://gitlab.freedesktop.org/xorg/xserver/-/commit/e56f61c79fc3cee26d83cda0f84ae56d5979f768
- https://security-tracker.debian.org/tracker/CVE-2021-4011
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-4011
- https://www.openwall.com/lists/oss-security/2021/12/14/1
- https://ubuntu.com/security/notices/USN-5193-1
- https://ubuntu.com/security/notices/USN-5193-2
- https://ubuntu.com/security/notices/USN-5193-3
- https://nvd.nist.gov/vuln/detail/CVE-2021-4011
- https://ubuntu.com/security/CVE-2021-4011
Frequently Asked Questions
What is CVE-2021-4011?
CVE-2021-4011 is a vulnerability that allows local attackers to escalate privileges on affected installations of X.Org Server.
How can this vulnerability be exploited?
An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability.
What is the severity of CVE-2021-4011?
CVE-2021-4011 has a severity rating of 7.8 (High).
Which versions of X.Org Server are affected by CVE-2021-4011?
Versions up to and including 21.1.2 of X.Org Server are affected by CVE-2021-4011.
How can I fix CVE-2021-4011?
To fix CVE-2021-4011, update X.Org Server to version 21.1.2 or later.
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