CVE-2021-43238: Microsoft Windows Remote Access Connection Manager Service Link Following Denial-of-Service Vulnerability
First published: Tue Dec 14 2021(Updated: )
This vulnerability allows local attackers to create a denial-of-service condition on affected installations of Microsoft Windows. 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 Remote Access Connection Manager service. By creating a directory junction, an attacker can abuse the service to create a directory. An attacker can leverage this vulnerability to create a denial-of-service condition on the system.
Credit: secure@microsoft.com secure@microsoft.com
| Affected Software | Affected Version | How to fix |
|---|---|---|
| Microsoft Windows 10 | =20H2 | |
| Microsoft Windows | ||
| Microsoft Windows 10 | =1909 | |
| Microsoft Windows 10 | =2004 | |
| Microsoft Windows 10 | =21H1 | |
| Microsoft Windows Server 2022 | ||
| Microsoft Windows 10 | =20H2 | |
| Microsoft Windows Server 2012 R2 | ||
| Microsoft Windows 8.1 for x64-based systems | ||
| Microsoft Windows 10 | =1809 | |
| Microsoft Windows 10 | =1607 | |
| Microsoft Windows 10 | =1607 | |
| Microsoft Windows Server 2012 R2 | ||
| Microsoft Windows Server 2016 | ||
| Microsoft Windows 10 | =2004 | |
| Microsoft Windows 10 | =1909 | |
| Microsoft Windows 10 | =2004 | |
| Microsoft Windows Server 2022 | ||
| Microsoft Windows Server 2008 R2 | ||
| Microsoft Windows 11 | =21H2 | |
| Microsoft Windows Server | =20H2 | |
| Microsoft Windows 10 | ||
| Microsoft Windows 10 | =20H2 | |
| Microsoft Windows Server 2016 | ||
| Microsoft Windows 7 | ||
| Microsoft Windows 10 | =21H1 | |
| Microsoft Windows 8.1 for 32-bit systems | ||
| Microsoft Windows 10 | =1909 | |
| Microsoft Windows Server 2008 R2 | ||
| Microsoft Windows Server 2019 | ||
| Microsoft Windows 11 | =21H2 | |
| Microsoft Windows 7 | ||
| Microsoft Windows 10 | =21H2 | |
| Microsoft Windows 10 | =21H2 | |
| Microsoft Windows Server | =2004 | |
| Microsoft Windows 10 | =21H2 | |
| Microsoft Windows Server 2019 | ||
| Microsoft Windows 10 | ||
| Microsoft Windows 10 | =21H1 | |
| Microsoft Windows 10 | =1809 | |
| Microsoft Windows 10 | =1809 | |
| Microsoft Windows Server 2012 x64 | ||
| Microsoft Windows Server 2012 x64 | ||
| Microsoft Windows RT | ||
| Microsoft Windows Server 2008 Itanium | ||
| Microsoft Windows Server 2008 Itanium | ||
| Microsoft Windows 10 | ||
| Microsoft Windows 10 | ||
| Microsoft Windows 10 | =20h2 | |
| Microsoft Windows 10 | =20h2 | |
| Microsoft Windows 10 | =20h2 | |
| Microsoft Windows 10 | =21h1 | |
| Microsoft Windows 10 | =21h1 | |
| Microsoft Windows 10 | =21h1 | |
| Microsoft Windows 10 | =21h2 | |
| Microsoft Windows 10 | =21h2 | |
| Microsoft Windows 10 | =21h2 | |
| Microsoft Windows 10 | =1607 | |
| Microsoft Windows 10 | =1607 | |
| Microsoft Windows 10 | =1809 | |
| Microsoft Windows 10 | =1809 | |
| Microsoft Windows 10 | =1809 | |
| Microsoft Windows 10 | =1909 | |
| Microsoft Windows 10 | =1909 | |
| Microsoft Windows 10 | =1909 | |
| Microsoft Windows 10 | =2004 | |
| Microsoft Windows 10 | =2004 | |
| Microsoft Windows 10 | =2004 | |
| Microsoft Windows 11 | ||
| Microsoft Windows 11 | ||
| Microsoft Windows 7 | =sp1 | |
| Microsoft Windows 7 | =sp1 | |
| Microsoft Windows 8.1 | ||
| Microsoft Windows 8.1 | ||
| Microsoft Windows RT | ||
| Microsoft Windows Server | =20h2 | |
| Microsoft Windows Server | =2022 | |
| Microsoft Windows Server 2008 Itanium | =sp2 | |
| Microsoft Windows Server 2008 Itanium | =r2-sp1 | |
| Microsoft Windows Server 2012 x64 | ||
| Microsoft Windows Server 2012 x64 | =r2 | |
| Microsoft Windows Server 2016 | ||
| Microsoft Windows Server 2016 | =2004 | |
| Microsoft Windows Server 2019 | ||
| Microsoft Windows Server 2008 Itanium | ||
| Microsoft Windows Server 2008 Itanium |
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Reference Links
Frequently Asked Questions
What is the severity of CVE-2021-43238?
CVE-2021-43238 is classified as a denial-of-service vulnerability that can be exploited by local attackers on affected Microsoft Windows installations.
How do I fix CVE-2021-43238?
To fix CVE-2021-43238, apply the relevant security updates or patches provided by Microsoft for your specific version of Windows.
Which versions of Windows are affected by CVE-2021-43238?
CVE-2021-43238 affects multiple versions of Microsoft Windows, including various editions of Windows 10, Windows 11, and Windows Server.
What are the consequences of exploiting CVE-2021-43238?
Exploitation of CVE-2021-43238 can lead to a denial-of-service condition, causing affected systems to become unresponsive.
Is user interaction required to exploit CVE-2021-43238?
Yes, an attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit CVE-2021-43238.
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- canonical/microsoft windows server 2022
- canonical/microsoft windows server 2012 r2
- canonical/microsoft windows 8.1 for x64-based systems
- version/microsoft windows 10/1809
- version/microsoft windows 10/1607
- canonical/microsoft windows server 2016
- canonical/microsoft windows server 2008 r2
- canonical/microsoft windows 11
- version/microsoft windows 11/21h2
- canonical/microsoft windows server
- version/microsoft windows server/20h2
- canonical/microsoft windows 7
- canonical/microsoft windows 8.1 for 32-bit systems
- canonical/microsoft windows server 2019
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- version/microsoft windows server/2004
- canonical/microsoft windows server 2012 x64
- canonical/microsoft windows rt
- canonical/microsoft windows server 2008 itanium
- version/microsoft windows 7/sp1
- canonical/microsoft windows 8.1
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- version/microsoft windows server 2008 itanium/sp2
- version/microsoft windows server 2008 itanium/r2-sp1
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- version/microsoft windows server 2016/2004