CRITICALCVSS v3.1 9.8Actively exploited · CISA KEV since 2022-04-06Vulnerability
CVE-2021-31166
Microsoft HTTP Protocol Stack contains a vulnerability in http.sys that allows for remote code execution.
Properties
- Euvd product
- Windows 10 Version 2004, Windows Server version 2004, Windows Server version 20H2, Windows 10 Version 20H2
- Vulnerability name
- Microsoft HTTP Protocol Stack Remote Code Execution Vulnerability
- First seen
- 2025-10-21T23:25:45+00:00
- Cvss score
- 9.8
- Epss score
- 0.99867
- Last seen
- 2026-10-19T12:00:27+00:00
- Due date
- 2022-04-27
- Euvd assigner
- microsoft
- Retrieved at
- 2026-10-21T01:24:47+00:00
- Exploited euvd since
- 2022-04-06T00:00:00+00:00
- Src batch id
- epss_history-20261020T103617Z-728ddd
- Source url
- https://epss.empiricalsecurity.com/epss_scores-2026-10-19.csv.gz
- Date added
- 2022-04-06
- Score
- 9.8
- Euvd base score version
- 3.1
- Fetched at
- 2026-10-20T10:36:20+00:00
- Euvd vendor
- Microsoft
- Cvss vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- In Signal since
- initial import (Sep 2026)
- Euvd base score
- 9.8
Related Entities (7)
AFFECTS_PRODUCT (4)
DESCRIBES (1)
HAS_WEAKNESS (1)
INVOLVES (1)
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