CVE-2021-31166 - Vulnerability Details - OpenCVE

HTTP Protocol Stack Remote Code Execution Vulnerability

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact Partial

Integrity Impact Partial

Availability Impact Partial

This CVE is in the KEV database since April 6, 2022.

Exploitation active

Automatable yes

Technical Impact total

Vendors	Products
Microsoft	Windows 10 1809 Windows 10 2004 Windows 10 20h2 Windows 10 20h2 Windows Server 2004 Windows Server 20h2 Windows Server 20h2

Configuration 1 [-]

OR	cpe:2.3:o:microsoft:windows_10_2004::::::::
	cpe:2.3:o:microsoft:windows_10_20h2::::::::
	cpe:2.3:o:microsoft:windows_server_2004::::::::
	cpe:2.3:o:microsoft:windows_server_20h2::::::::

No data.

References

Link	Providers
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

History

Wed, 22 Oct 2025 00:15:00 +0000

Type	Values Removed	Values Added
References		https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31166

Tue, 21 Oct 2025 20:30:00 +0000

Type	Values Removed	Values Added
References	https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31166

Tue, 21 Oct 2025 19:30:00 +0000

Type	Values Removed	Values Added
References		https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31166

Fri, 07 Feb 2025 15:15:00 +0000

Type	Values Removed	Values Added
Metrics		kev `{'dateAdded': '2022-04-06'}` ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'active', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2021-05-11T19:11:19.000Z

Updated: 2025-10-21T23:25:45.988Z

Reserved: 2021-04-14T00:00:00.000Z

Link: CVE-2021-31166

Vulnrichment

Updated: 2024-08-03T22:55:52.129Z

NVD

Status : Analyzed

Published: 2021-05-11T19:15:09.300

Modified: 2025-10-30T19:55:18.167

Link: CVE-2021-31166

Redhat

No data.

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