Vulnerability Intelligence Report
HTTP Protocol Stack Remote Code Execution Vulnerability
CVE-2021-31166
HTTP Protocol Stack Remote Code Execution Vulnerability
CISA KEV
SSVC: Active Exploitation
Automatable
CVSS Base Score
9.8
CRITICAL
Exploitability:3.9
Impact Score:5.9
EPSS Probability:99.66%
Executive Threat Verdict
Evaluating...
Evaluating Threat Landscape...
Assessing known weaponization, exploitation telemetry, and federal advisories.
Attack Surface
—
Authentication
—
Weaponization
—
SSVC Action
—
Weaknesses (CWE)
CWE-416 ↗CWE-416 Use After Free
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| Microsoft | Windows 10 Version 2004 | 10.0.0 < 10.0.19041.982 (affected) |
| Microsoft | Windows Server version 2004 | 10.0.0 < 10.0.19041.982 (affected) |
| Microsoft | Windows 10 Version 20H2 | 10.0.0 < 10.0.19042.982 (affected) |
| Microsoft | Windows Server version 20H2 | 10.0.0 < 10.0.19042.982 (affected) |
References & Technical Advisories
No reference links found.
Threat Intelligence Signals
Identity & Timeline
| Status | PUBLISHED |
| Assigning Authority | Microsoft Corporation · Vendor · USA |
| Reserved | 2021-04-14T00:00:00 |
| Published | 2021-05-11T19:11:19 |
| Patch Date | 2021-05-11 |
| Last Updated | 2025-10-21T23:25:45 |
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