CVE-2021-43238: Microsoft Windows Remote Access Connection Manager Service Link Following Denial-of-Service Vulnerability

Published 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.

Other sources

Windows Remote Access Elevation of Privilege Vulnerability

Affected Software

86 affected componentsFixes available
Microsoft Windows Server 2012 R2
Microsoft Windows Server 2012 R2
Microsoft Windows Server=20H2
Microsoft Windows Server=2004
Microsoft Windows RT 8.1
Microsoft Windows Server 2012
Microsoft Windows Server 2012
Microsoft Windows Server 2008
Microsoft Windows Server 2008
Microsoft Windows Server 2008
Microsoft Windows Server 2008
Microsoft Windows 8.1 for x64-based systems
Microsoft Windows 8.1 for 32-bit systems
Microsoft Windows Server 2019
Microsoft Windows Server 2019
Microsoft Windows 11=21H2
Microsoft Windows 11=21H2
Microsoft Windows Server 2022
Microsoft Windows Server 2022
Microsoft Windows Server 2016
Microsoft Windows Server 2016
Microsoft Windows 10=20H2
Microsoft Windows 10=20H2
Microsoft Windows 10=20H2
Microsoft Windows 10=1809
Microsoft Windows 10=1809
Microsoft Windows 10=1809
Microsoft Windows 10=1607
Microsoft Windows 10=1607
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=1909
Microsoft Windows 10=1909
Microsoft Windows 10=1909
Microsoft Windows 10
Microsoft Windows 10
Microsoft Windows 10=2004
Microsoft Windows 10=2004
Microsoft Windows 10=2004
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 8.1
Microsoft Windows Server=20h2
Microsoft Windows Server=2022
Microsoft Windows Server 2008=sp2
Microsoft Windows Server 2008=r2-sp1
Microsoft Windows Server 2012
Microsoft Windows Server 2012=r2
Microsoft Windows Server 2016
Microsoft Windows Server 2016=2004
Microsoft Windows Server 2019
Microsoft Windows
Microsoft Windows Server 2008 R2
Microsoft Windows Server 2008 R2

Event History

Dec 14, 2021
CVE Published
via Microsoft·08:00 AM
Data Sourced
via Microsoft·08:00 AM
DescriptionSeverityWeakness
Dec 15, 2021
CVE Published
via MITRE·02:15 PM
Data Sourced
via MITRE·02:15 PM
DescriptionSeverity
Apr 1, 2025
Advisory Published
via ZDI·05:16 PM

Frequently Asked Questions

1

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.

2

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.

3

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.

4

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.

5

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.

Contact

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