Microsoft Windows SAM Local Privilege Escalation Vulnerability

Added to KEV
2022-02-10
Federal due date
2022-02-24
Vendor
Microsoft
Product
Windows
EPSS
99.6th percentile (score 0.904, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Unknown
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2021-36934

CISA short description

If a Volume Shadow Copy (VSS) shadow copy of the system drive is available, users can read the SAM file which would allow any user to escalate privileges to SYSTEM level.

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.