CVE-2026-40366

Estado: ModificadaAlta (8.4)—

Access of resource using incompatible type ('type confusion') in Microsoft Office Word allows an unauthorized attacker to execute code locally.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 8.4

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.36%
Percentil entre todas las CVEs puntuadas: 28
Fecha de la puntuación: 4/10/2026

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).

🎯 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 escalation90 %
Impacto principalT1059 Command and Scripting Interpreterexecution85 %

AV:L, PR:N, UI:N → escalada local sin interacción. Type confusion en Word permite ejecución de código con privilegios elevados (CWE-416, acceso a memoria incompatible).

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

Execution Prevention Threat Intelligence Program Restrict Web-Based Content Privileged Account Management Limit Software Installation Behavior Prevention on Endpoint

Tecnologías afectadas (4)

Microsoft — 365 Apps Microsoft — Office Microsoft — Office Long Term Servicing Channel Microsoft — Word

CWE

CWE-416

Referencias

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40366

JSON original (NVD)

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