CVE-2021-31961

Windows InstallService Elevation of Privilege Vulnerability

Description

Windows InstallService Elevation of Privilege Vulnerability

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.32%
Vendor Advisory microsoft.com
Affected: Microsoft Windows 10 Version 1809
Affected: Microsoft Windows Server 2019
Affected: Microsoft Windows Server 2019 (Server Core installation)
Affected: Microsoft Windows 10 Version 1909
Affected: Microsoft Windows 10 Version 21H1
Affected: Microsoft Windows 10 Version 2004
Affected: Microsoft Windows Server version 2004
Affected: Microsoft Windows 10 Version 20H2
Affected: Microsoft Windows Server version 20H2
Published at:
Updated at:

References

Link Tags
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31961 patch vendor advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-818/ vdb entry third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-31961?
CVE-2021-31961 has been scored as a medium severity vulnerability.
How to fix CVE-2021-31961?
To fix CVE-2021-31961, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-31961 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-31961 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-31961?
CVE-2021-31961 affects Microsoft Windows 10 Version 1809, Microsoft Windows Server 2019, Microsoft Windows Server 2019 (Server Core installation), Microsoft Windows 10 Version 1909, Microsoft Windows 10 Version 21H1, Microsoft Windows 10 Version 2004, Microsoft Windows Server version 2004, Microsoft Windows 10 Version 20H2, Microsoft Windows Server version 20H2.
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