CVE-2021-31166 KEV
9.8
CRITICAL · CVSS 3.1 · EPSS 99.8% (pctl 100)
Patch first
On CISA KEV — known exploited in the wild, due 2022-04-27.
Description
HTTP Protocol Stack Remote Code Execution Vulnerability
Scoring
| CVSS | 9.8 (CRITICAL, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 99.77% — more likely to be exploited than 100% of all CVEs |
| Weakness | CWE-416 |
| On CISA KEV | yes — remediate by 2022-04-27 |
| Public exploit | none known |
| Published | 2021-05-11 |
| Last modified | 2026-06-17 |
CISA KEV
| Name | Microsoft HTTP Protocol Stack Remote Code Execution Vulnerability |
|---|---|
| Added | 2022-04-06 |
| Due | 2022-04-27 |
| Vendor / product | Microsoft / HTTP Protocol Stack |
| Ransomware use | none reported |
Affected (4)
| Vendor | Product |
|---|---|
| microsoft | windows 10 2004 |
| microsoft | windows 10 20h2 |
| microsoft | windows server 2004 |
| microsoft | windows server 20h2 |
References
- http://packetstormsecurity.com/files/162722/Microsoft-HTTP-Protocol-Stack-Remote-Code-Execution.html
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31166
- http://packetstormsecurity.com/files/162722/Microsoft-HTTP-Protocol-Stack-Remote-Code-Execution.html
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31166
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31166
→ the Explorer · watch your stack · NVD