Actively exploited
Listed in CISA’s Known Exploited Vulnerabilities catalog since February 10, 2026.
CVE-2026-21533
Microsoft Windows Improper Privilege Management Vulnerability
Added to KEV February 10, 2026
Alert details
- Source feed
- CISA KEV
- CVE ID
- CVE-2026-21533
- CWE
- CWE-269
- Affected products
- Windows · Microsoft Windows · Microsoft
What happened
Microsoft Windows Remote Desktop Services contains an improper privilege management vulnerability that could allow an authorized attacker to elevate privileges locally.
What it means for your business
Microsoft Windows is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2026-21533). Microsoft Windows Remote Desktop Services contains an improper privilege management vulnerability that could allow an authorized attacker to elevate privileges locally. CISA remediation due date: 2026-03-03. If you need help checking exposure, call (864) 335-9223.
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.
CISA due date: March 3, 2026
Sources
Related briefs
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