known ransomware use

Microsoft Active Directory Domain Services Privilege Escalation Vulnerability

Added to KEV
2022-04-11
Federal due date
2022-05-02
Vendor
Microsoft
Product
Active Directory
EPSS
99.9th percentile (score 0.940, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Known
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2021-42287

CISA short description

Microsoft Active Directory Domain Services contains an unspecified vulnerability that allows for privilege escalation.

Required action

Apply updates per vendor instructions.

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.