April 6, 2022 · Applied Cybernetics Group
CVE-2021-31166 — Microsoft HTTP Protocol Stack
Microsoft HTTP Protocol Stack Remote Code Execution Vulnerability
- Added to KEV
2022-04-06- Federal due date
2022-04-27- Vendor
- Microsoft
- Product
- HTTP Protocol Stack
- EPSS
- 100.0th percentile (score 0.998, as of
2026-09-16) - NVD CVSS v3.1
- —
- Ransomware use
- Unknown
- ATT&CK
- T1059 , T1190 · signal rollup
- Upstream
- https://nvd.nist.gov/vuln/detail/CVE-2021-31166
CISA short description
Microsoft HTTP Protocol Stack contains a vulnerability in http.sys that allows for remote code execution.
Required action
Apply updates per vendor instructions.