CVE-2026-21533

Published: Feb 10, 2026Modified: Mar 30, 2026CISA KEV

7.8

Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Exploitability: 1.8 / Impact: 5.9

Source: secure@microsoft.com (Secondary)

Description

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

Affected (23)

Products: Microsoft: Windows 10 1607, Windows 10 1809, Windows 10 21h2, Windows 10 22h2, Windows 11 23h2, Windows 11 24h2, Windows 11 25h2, Windows Server 2012, Windows Server 2016, Windows Server 2019, Windows Server 2022, Windows Server 2022 23h2, Windows Server 2025

13 products

Windows 10 1607

Windows 10 1809

Windows 10 21h2

Windows 10 22h2

Windows 11 23h2

Windows 11 24h2

Windows 11 25h2

Windows Server 2012

Windows Server 2016

Windows Server 2019

Windows Server 2022

Windows Server 2022 23h2

Windows Server 2025

Configuration A

23 vulnerable

Vulnerable Software	Affected Versions
Microsoft Windows 10 1607	Before 10.0.14393.8868
Microsoft Windows 10 1607	Before 10.0.14393.8868
Microsoft Windows 10 1809	Before 10.0.17763.8389
Microsoft Windows 10 1809	Before 10.0.17763.8389
Microsoft Windows 10 21h2	Before 10.0.19044.6937
Microsoft Windows 10 21h2	Before 10.0.19044.6937
Microsoft Windows 10 21h2	Before 10.0.19044.6937
Microsoft Windows 10 22h2	Before 10.0.19045.6937
Microsoft Windows 10 22h2	Before 10.0.19045.6937
Microsoft Windows 10 22h2	Before 10.0.19045.6937
Microsoft Windows 11 23h2	Before 10.0.22631.6649
Microsoft Windows 11 23h2	Before 10.0.22631.6649
Microsoft Windows 11 24h2	Before 10.0.26100.7781
Microsoft Windows 11 24h2	Before 10.0.26100.7781
Microsoft Windows 11 25h2	Before 10.0.26200.7781
Microsoft Windows 11 25h2	Before 10.0.26200.7781
Microsoft Windows Server 2012	All versions
Microsoft Windows Server 2012	Version r2
Microsoft Windows Server 2016	Before 10.0.14393.8868
Microsoft Windows Server 2019	Before 10.0.17763.8389
Microsoft Windows Server 2022	Before 10.0.20348.4711
Microsoft Windows Server 2022 23h2	Before 10.0.25398.2149
Microsoft Windows Server 2025	Before 10.0.26100.32313

Related CWEs

Improper Privilege Management

The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.

References (4)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21533

Source: secure@microsoft.com

Vendor Advisory

https://www.vicarius.io/vsociety/posts/cve-2026-21533-detection-script-privilege-escalation-vulnerability-in-windows-remote-desktop

Source: af854a3a-2127-422b-91ae-364da2661108

Third Party Advisory

https://www.vicarius.io/vsociety/posts/cve-2026-21533-mitigation-script-privilege-escalation-vulnerability-in-windows-remote-desktop

Source: af854a3a-2127-422b-91ae-364da2661108

MitigationThird Party Advisory

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-21533

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

US Government Resource

Timeline

No history available yet.