MEDIUM CISA KEV Actively Exploited

CVE-2026-21525

Windows Remote Access Connection Manager Denial of Service Vulnerability

CVSS v3

6.2

MEDIUM

EPSS Score

4.8 %

exploit probability, as of 2026-10-04

CISA KEV

Yes

known exploited

Exploitation

active

SSVC status

Description

Null pointer dereference in Windows Remote Access Connection Manager allows an unauthorized attacker to deny service locally.

CISA Known Exploited Vulnerability

Date Added: 2026-02-10
Patch Due Date: 2026-03-03
Ransomware Use: Unknown

Technical details

Published: 2026-02-10
Last Modified: 2026-03-30

Frequently asked questions

What is CVE-2026-21525?

Null pointer dereference in Windows Remote Access Connection Manager allows an unauthorized attacker to deny service locally.

Is CVE-2026-21525 actively exploited?

Yes. CVE-2026-21525 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 2026-03-03.

What is the CVSS score for CVE-2026-21525?

CVE-2026-21525 has a CVSS v3 base score of 6.2 (MEDIUM severity).

Is CVE-2026-21525 affecting your environment?

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