High7.8Microsoft Server Exploited CISA KEV

High [CVE-2026-21533] Windows Remote Desktop Services Elevation of Privilege Vulnerability

This high-severity Microsoft Server advisory covers CVE-2026-21533 affecting Windows Server 2012 (Server Core installation), Windows Server 2012 R2 (Server Core installation), Windows Server 2016 (Server Core installation).

CVE-2026-21533 Published Feb 10, 2026Updated by vendor Aug 19, 2026

CVE-2026-21533

Affected products & platforms

Microsoft ServerWindows Server

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Summary

Improper privilege management in Windows Remote Desktop allows an authorized attacker to elevate privileges locally.

Affected products named by the advisory: Windows Server 2012; Windows Server 2012 (Server Core installation); Windows Server 2012 R2; Windows Server 2012 R2 (Server Core installation); and 8 more.

Affected products named by the advisory: Windows Server 2016 (Server Core installation); Windows Server 2019 (Server Core installation); Windows Server 2022, 23H2 Edition (Server Core installation); Windows Server 2025 (Server Core installation).

CISA Known Exploited Vulnerability

Listed:: Feb 10, 2026 · federal remediation due Mar 3, 2026
Required action:: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Ransomware use:: Unknown

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

Affected versions

Windows 10 Version 1607 10.0.14393.0 before 10.0.14393.8868
Windows 10 Version 1809 10.0.17763.0 before 10.0.17763.8389
Windows 10 Version 21H2 10.0.19044.0 before 10.0.19044.6937
Windows 10 Version 22H2 10.0.19045.0 before 10.0.19045.6937
Windows 11 version 22H3 10.0.22631.0 before 10.0.22631.6649
Windows 11 Version 23H2 10.0.22631.0 before 10.0.22631.6649
Windows 11 Version 24H2 10.0.26100.0 before 10.0.26100.7840
Windows 11 Version 25H2 10.0.26200.0 before 10.0.26200.7840
Windows 11 version 26H1 10.0.28000.0 before 10.0.28000.1575
Windows 11 Version 26H1 10.0.28000.0 before 10.0.28000.1575
Windows Server 2012 6.2.9200.0 before 6.2.9200.25923
Windows Server 2012 (Server Core installation) 6.2.9200.0 before 6.2.9200.25923

Official advisory · high-confidence parse· fetched 2 hours ago·verify at source

Fixed versions

10.0.14393.8868
10.0.17763.8389
10.0.19044.6937
10.0.19045.6937
10.0.22631.6649
10.0.26100.7840
10.0.26200.7840
10.0.28000.1575
6.2.9200.25923
6.3.9600.23022
10.0.20348.4773
10.0.25398.2149

Official advisory · high-confidence parse· fetched 2 hours ago·verify at source

Mitigation

Upgrade to a fixed release: 10.0.14393.8868, 10.0.17763.8389, 10.0.19044.6937, 10.0.19045.6937, 10.0.22631.6649, 10.0.26100.7840. 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 2 hours ago·verify at source

Discussion(0)

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