High7.5Microsoft Server Exploited CISA KEV

High [CVE-2021-42278] Active Directory Domain Services Elevation of Privilege Vulnerability

This high-severity Microsoft Server advisory covers CVE-2021-42278 affecting Windows Server 2019 (Server Core installation), Windows Server 2022, Windows Server version 2004.

CVE-2021-42278 Published Nov 10, 2021Updated by vendor Aug 6, 2026

CVE-2021-42278

Affected products & platforms

Microsoft ServerWindows Server

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Summary

Active Directory Domain Services Elevation of Privilege Vulnerability

Affected products named by the advisory: Windows Server 2019; Windows Server 2019 (Server Core installation); Windows Server 2022; Windows Server version 2004; and 11 more.

Affected products named by the advisory: Windows Server version 20H2; Windows Server 2016 (Server Core installation); Windows Server 2008 Service Pack 2 (Server Core installation); Windows Server 2008 Service Pack 2; and 3 more.

CISA Known Exploited Vulnerability

Listed:: Apr 11, 2022 · federal remediation due May 2, 2022
Required action:: Apply updates per vendor instructions.
Ransomware use:: Known

KEV is a prioritization signal from CISA — remediation detail still comes from the vendor advisory.

Affected versions

Windows Server 2019 10.0.0 before 10.0.17763.2300
Windows Server 2019 (Server Core installation) 10.0.0 before 10.0.17763.2300
Windows Server 2022 10.0.0 before 10.0.20348.350
Windows Server version 2004 10.0.0 before 10.0.19041.1348
Windows Server version 20H2 10.0.0 before 10.0.19042.1348
Windows Server 2016 10.0.0 before 10.0.14393.4770
Windows Server 2016 (Server Core installation) 10.0.0 before 10.0.14393.4770
Windows Server 2008 Service Pack 2 6.0.0 before 6.0.6003.21282
Windows Server 2008 Service Pack 2 (Server Core installation) 6.0.0 before 6.0.6003.21282
Windows Server 2008 Service Pack 2 6.0.0 before 6.0.6003.21282
Windows Server 2008 R2 Service Pack 1 6.1.0 before 6.1.7601.25769
Windows Server 2008 R2 Service Pack 1 (Server Core installation) 6.0.0 before 6.1.7601.25769

Official advisory · high-confidence parse· fetched 1 hour ago·verify at source

Fixed versions

10.0.17763.2300
10.0.20348.350
10.0.19041.1348
10.0.19042.1348
10.0.14393.4770
6.0.6003.21282
6.1.7601.25769
6.2.9200.23517
6.3.9600.20174

Official advisory · high-confidence parse· fetched 1 hour ago·verify at source

Mitigation

Upgrade to a fixed release: 10.0.17763.2300, 10.0.20348.350, 10.0.19041.1348, 10.0.19042.1348, 10.0.14393.4770, 6.0.6003.21282. That is the remediation for this advisory.

The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.

Official advisory · high-confidence parse· fetched 1 hour ago·verify at source

Discussion(0)

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