CVE-2021-31955

Estado: AnalizadaMedia (5.5)⚠ Explotación activa

Windows Kernel Information Disclosure Vulnerability

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Puntuación base: 5.5

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 81%
Percentil entre todas las CVEs puntuadas: 100
Fecha de la puntuación: 6/10/2026

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: 3/11/2021
Plazo de remediación: 17/11/2021
Uso conocido en ransomware: Unknown

🎯 Técnicas ATT&CK

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

ExplotaciónT1068 Exploitation for Privilege Escalationprivilege escalation95 %
Impacto principalT1005 Data from Local Systemcollection85 %
Impacto secundarioT1552.001 Credentials In Filescredential access80 %

Vulnerabilidad local de divulgación de información del kernel Windows (CWE-497) con requerimiento de privilegio local. Permite lectura de datos sensibles de memoria del kernel sin ejecución remota ni escalada de privilegios.

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

User Training Threat Intelligence Program Restrict File and Directory Permissions Password Policies Execution Prevention Audit

Tecnologías afectadas (8)

Microsoft — Windows 10 1809 Microsoft — Windows 10 1909 Microsoft — Windows 10 2004 Microsoft — Windows 10 20h2 Microsoft — Windows 10 21h1 Microsoft — Windows Server 2004 Microsoft — Windows Server 2019 Microsoft — Windows Server 20h2

CWE

NVD-CWE-noinfo
CWE-497

Referencias

JSON original (NVD)

Mostrar

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}