CVE-2021-31166
Microsoft HTTP Protocol Stack Remote Code Execution Vulnerability
Microsoft · HTTP Protocol Stack
Vulnerability details
Microsoft HTTP Protocol Stack contains a vulnerability in http.sys that allows for remote code execution.
Added to CISA KEV: 2022-04-06
Ransomware campaign use: Unknown
CISA due date: 2022-04-27
Defensive guidance from CISA
Apply updates per vendor instructions.
This is the source's required-action field, not an independently validated patch procedure. Refer to the vendor for exact affected versions and fixes.
Source catalog date: 2026-11-06T19:44:45.1797Z · Last retrieved: 2026-11-06 21:02:26 UTC