CVE-2021-31166

Estado: AnalizadaCrítica (9.8)⚠ Explotación activa💥 PoC

HTTP Protocol Stack Remote Code Execution Vulnerability

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 9.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 100%
Percentil entre todas las CVEs puntuadas: 100
Fecha de la puntuación: 29/9/2026

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

CISA KEV — explotada activamente

Añadida al catálogo: 6/4/2022
Plazo de remediación: 27/4/2022
Uso conocido en ransomware: Unknown

💥 Exploits públicos

Hay código de explotación o plantillas de detección públicos. No es lo mismo que explotación activa confirmada (KEV), pero aumenta el riesgo: parchee con prioridad.

Prueba de concepto en GitHub (no verificada) · Lista de pruebas de concepto en GitHub

⚠️ Las pruebas de concepto de GitHub no están verificadas: algunas son falsas o contienen malware. No las ejecute nunca fuera de un laboratorio aislado.

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access95 %
Impacto principalT1059 Command and Scripting Interpreterexecution90 %
Impacto secundarioT1498.001 Direct Network Floodimpact70 %

CVE-2021-31166 es una RCE en HTTP.sys (stack HTTP remoto) con vector AV:N/AC:L/PR:N. CWE-416 (use-after-free) permite ejecución remota sin autenticación, explotable directamente contra servicio expuesto. Impacto: ejecución arbitraria de comandos T1059 y potencial DoS T1498.001 por manipulación de pr

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Privileged Account Management Filter Network Traffic Vulnerability Scanning Restrict Web-Based Content Network Segmentation Limit Software Installation

Tecnologías afectadas (4)

Microsoft — Windows 10 2004 Microsoft — Windows 10 20h2 Microsoft — Windows Server 2004 Microsoft — Windows Server 20h2

CWE

CWE-416
CWE-416

Referencias

JSON original (NVD)

Mostrar

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