November 17, 2021 · Applied Cybernetics Group
CVE-2021-40449 — Microsoft Windows
known ransomware use
Microsoft Windows Win32k Privilege Escalation Vulnerability
- Added to KEV
2021-11-17- Federal due date
2021-12-01- Vendor
- Microsoft
- Product
- Windows
- EPSS
- 99.4th percentile (score 0.734, as of
2026-07-13) - NVD CVSS v3.1
- —
- Ransomware use
- Known
- ATT&CK
- T1016 , T1027 , T1059.003 , T1068 , T1071.001 , T1082 , T1566 , T1573.001 · signal rollup
- Upstream
- https://nvd.nist.gov/vuln/detail/CVE-2021-40449
CISA short description
Unspecified vulnerability allows for an authenticated user to escalate privileges.
Required action
Apply updates per vendor instructions.