CVE-2026-21525

Microsoft Windows — Microsoft Windows NULL Pointer Dereference Vulnerability
⚠️ CVSS 3.1  6.2 / 10 — MEDIUM 🔴 CISA Known Exploited Vulnerability

Overview

Microsoft Windows Remote Access Connection Manager contains a NULL pointer dereference that could allow an unauthorized attacker to deny service locally.

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21525 ; https://nvd.nist.gov/vuln/detail/CVE-2026-21525

Key Details

PropertyValue
CVE ID CVE-2026-21525
Vendor / Product Microsoft — Windows
NVD Published2026-02-10
NVD Last Modified2026-03-30
CVSS 3.1 Score6.2
CVSS 3.1 VectorCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SeverityMEDIUM
CWE CWE-476
CISA KEV Added2026-02-10
CISA KEV Deadline2026-03-03
Known Ransomware Use No

CVSS 3.1 Breakdown

Attack Vector
Local
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Required Action

CISA BOD 22-01 Deadline: 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.

Timeline

DateEvent
2026-02-10Added to CISA Known Exploited Vulnerabilities catalog
2026-03-03CISA BOD 22-01 remediation deadline

References

ResourceType
NVD — CVE-2026-21525 Vulnerability Database
CISA KEV Catalog Entry US Government