December 15, 2021 · Applied Cybernetics Group
CVE-2021-43890 — Microsoft Windows
known ransomware use
Microsoft Windows AppX Installer Spoofing Vulnerability
- Added to KEV
2021-12-15- Federal due date
2021-12-29- Vendor
- Microsoft
- Product
- Windows
- EPSS
- 96.3th percentile (score 0.252, as of
2026-06-08) - NVD CVSS v3.1
- —
- Ransomware use
- Known
- Upstream
- https://nvd.nist.gov/vuln/detail/CVE-2021-43890
CISA short description
Microsoft Windows AppX Installer contains a spoofing vulnerability which has a high impacts to confidentiality, integrity, and availability.
Required action
Apply updates per vendor instructions.