CVEvulnerability

CVE-2021-31166

9.8 CRITICAL Known exploited Published 2021-05-11 Modified 2026-06-17 Official page ↗

CISA Known Exploited Vulnerability

Microsoft HTTP Protocol Stack Remote Code Execution Vulnerability — Microsoft HTTP Protocol Stack

Microsoft HTTP Protocol Stack contains a vulnerability in http.sys that allows for remote code execution.

Added to KEV: 2022-04-06
Remediation due: 2022-04-27
Ransomware use: Unknown
Required action: Apply updates per vendor instructions.
Notes: https://nvd.nist.gov/vuln/detail/CVE-2021-31166

Status: Analyzed
Published: 2021-05-11
Last modified: 2026-06-17
Assigner: [email protected]
CVSS 3.1 ([email protected]): 9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 3.1 ([email protected]): 9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.0 ([email protected]): 7.5 HIGH — AV:N/AC:L/Au:N/C:P/I:P/A:P
Weaknesses: CWE-416

Description

HTTP Protocol Stack Remote Code Execution Vulnerability

Affected configurations

• microsoft windows 10 2004 (< 10.0.19041.982) • microsoft windows 10 20h2 (< 10.0.19042.982) • microsoft windows server 2004 (< 10.0.19041.982) • microsoft windows server 20h2 (< 10.0.19042.982)

Weakness · CWE (1)

CWE-416 Use After Free weakness

References