CVE-2021-36942Actively exploitedAdded to KEV 2021-11-03Known ransomware campaign use

Microsoft Windows Local Security Authority (LSA) Spoofing Vulnerability

Microsoft, Windows

Description

Microsoft Windows Local Security Authority (LSA) contains a spoofing vulnerability allowing an unauthenticated attacker to call a method on the LSARPC interface and coerce the domain controller to authenticate against another server using NTLM.

CVSS severity for this advisory hasn't been enriched from NVD yet, check back shortly.

EPSS, exploit probability

Critical

66.0%

estimated chance of real-world exploitation in the next 30 days, higher than 99.3% of every CVE FIRST.org scores

Refreshed 10/28/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.

Required action

Apply updates per vendor instructions.

CISA-recommended due date: 2021-11-17

CWE-749

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