HIGH CISA KEV Actively Exploited

CVE-2026-21533

Windows Remote Desktop Services Elevation of Privilege Vulnerability

CVSS v3

7.8

HIGH

EPSS Score

20.2%

exploit probability

CISA KEV

Yes

known exploited

Exploitation

active

SSVC status

Description

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

CISA Known Exploited Vulnerability

Date Added
2/10/2026
Patch Due Date
3/3/2026
Ransomware Use
Unknown

Technical details

CVSS v3 Vector
3.1
Published
2/10/2026
Last Modified
3/30/2026

Frequently asked questions

What is CVE-2026-21533?

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

Is CVE-2026-21533 actively exploited?

Yes. CVE-2026-21533 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 3/3/2026.

What is the CVSS score for CVE-2026-21533?

CVE-2026-21533 has a CVSS v3 base score of 7.8 (HIGH severity), with vector string 3.1.

Is CVE-2026-21533 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.