high7.8Known exploited
CVE-2026-21533
Microsoft Windows Improper Privilege Management Vulnerability
Exploited in the wild
This vulnerability is on the CISA Known Exploited Vulnerabilities list, added 2026-02-10. Federal due date: 2026-03-03.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Impact
Microsoft Windows Remote Desktop Services contains an improper privilege management vulnerability that could allow an authorized attacker to elevate privileges locally.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Microsoft | Windows 10 1607 | before 10.0.14393.8868 |
| Microsoft | Windows 10 1809 | before 10.0.17763.8389 |
| Microsoft | Windows 10 21h2 | before 10.0.19044.6937 |
| Microsoft | Windows 10 22h2 | before 10.0.19045.6937 |
| Microsoft | Windows 11 23h2 | before 10.0.22631.6649 |
| Microsoft | Windows 11 24h2 | before 10.0.26100.7781 |
| Microsoft | Windows 11 25h2 | before 10.0.26200.7781 |
| Microsoft | Windows Server 2012 | All versions 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 |
Weakness classification
References
- NVD record
- CVE.org record
- CISA KEV catalog
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21533
- https://www.vicarius.io/vsociety/posts/cve-2026-21533-detection-script-privilege-escalation-vulnerability-in-windows-remote-desktop
- https://www.vicarius.io/vsociety/posts/cve-2026-21533-mitigation-script-privilege-escalation-vulnerability-in-windows-remote-desktop
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-21533