CVE-2021-27070: Microsoft Windows Update Assistant Improper Access Control Privilege Escalation Vulnerability

Published Mar 9, 2021
·
Updated

Windows 10 Update Assistant Elevation of Privilege Vulnerability

Other sources

This vulnerability allows local attackers to escalate privileges 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 Windows Update Assistant. The issue results from incorrect permissions on a directory. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of Administrator.

ZDI

Affected Software

13 affected componentsFixes available
Microsoft Windows Server=20H2
Microsoft Windows Server=2004
Microsoft Windows 10=20H2
Microsoft Windows 10=20H2
Microsoft Windows 10=20H2
Microsoft Windows 10=2004
Microsoft Windows 10=2004
Microsoft Windows 10=2004
Microsoft Windows 10=20h2
Microsoft Windows 10=2004
Microsoft Windows Server 2016=20h2
Microsoft Windows Server 2016=2004
Microsoft Windows

Event History

Mar 9, 2021
CVE Published
via Microsoft·08:00 AM
Data Sourced
via Microsoft·08:00 AM
DescriptionSeverityWeakness
Mar 11, 2021
CVE Published
via MITRE·03:49 PM
Data Sourced
via MITRE·03:49 PM
DescriptionSeverity
Apr 1, 2025
Advisory Published
via ZDI·05:16 PM

Frequently Asked Questions

1

What is CVE-2021-27070?

CVE-2021-27070 is a vulnerability in Microsoft Windows that allows local attackers to escalate privileges on affected installations.

2

What is the severity of CVE-2021-27070?

The severity of CVE-2021-27070 is critical, with a CVSS score of 7.8.

3

How can an attacker exploit CVE-2021-27070?

An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit CVE-2021-27070.

4

Which software versions are affected by CVE-2021-27070?

CVE-2021-27070 affects Microsoft Windows 10 versions 20H2 and 2004, as well as Windows Server 2016 versions 20H2 and 2004.

5

How can I fix CVE-2021-27070?

To fix CVE-2021-27070, apply the necessary patches provided by Microsoft, which can be found at the provided URLs.

Contact

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