CVE-2021-31166

HTTP Protocol Stack Remote Code Execution Vulnerability

State: Published
Severity: 9.8 Critical
Published: May 11, 2021
Updated: Oct 21, 2025
Reserved: Apr 14, 2021

Description

HTTP Protocol Stack Remote Code Execution Vulnerability

Scores

CVSS	Score	Vector	Source
3.1	9.8 Critical	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C	microsoft

Weaknesses

CWE-416 Use After Free

Affected Products

Product	Versions
Windows 10 Version 2004Microsoft	10.0.0 to before 10.0.19041.982Affected
Windows Server version 2004Microsoft	10.0.0 to before 10.0.19041.982Affected
Windows 10 Version 20H2Microsoft	10.0.0 to before 10.0.19042.982Affected
Windows Server version 20H2Microsoft	10.0.0 to before 10.0.19042.982Affected

References

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://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31166government-resource

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