CVE-2021-33742
Estado: AnalizadaAlta (8.8)⚠ Explotación activa
Windows MSHTML Platform Remote Code Execution Vulnerability
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Puntuación base: 8.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 59%
- Percentil entre todas las CVEs puntuadas: 99
- 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.
- Explotación
T1203Exploitation for Client Executionexecution85 % - Impacto principal
T1059Command and Scripting Interpreterexecution90 %
Vulnerabilidad MSHTML (CWE-787, escritura fuera de límites) requiere interacción del usuario (UI:R) para exploración remota. Permite ejecución de código remoto con permisos de usuario (C:H/I:H/A:H).
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
Tecnologías afectadas (14)
Microsoft — Windows 10 1507Microsoft — Windows 10 1607Microsoft — Windows 10 1809Microsoft — Windows 10 1909Microsoft — Windows 10 2004Microsoft — Windows 10 20h2Microsoft — Windows 10 21h1Microsoft — Windows 7Microsoft — Windows 8.1Microsoft — Windows RT 8.1Microsoft — Windows Server 2008Microsoft — Windows Server 2012Microsoft — Windows Server 2016Microsoft — Windows Server 2019
CWE
- CWE-787
- CWE-787
Referencias
JSON original (NVD)
Mostrar
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"published": "2021-06-08T23:15:09.540",
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}