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CVE-2026-55949

Estado: AnalizadaAlta (7.8)—

Use of uninitialized resource in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVSS

Probabilidad de explotación (EPSS)

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.

Vector CVSS con AV:L y UI:R (interacción del usuario abriendo archivo) indica ejecución en el cliente. CWE-908 (recurso no inicializado) en Excel permite ejecución de código local. Potencial acceso a datos (C:H, I:H) como impactos secundarios.

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

Restrict Web-Based ContentPrivileged Account ManagementLimit Software InstallationExecution PreventionBehavior Prevention on EndpointDisable or Remove Feature or Program

Tecnologías afectadas (7)

Microsoft — 365 AppsMicrosoft — ExcelMicrosoft — Microsoft 365Microsoft — Office 2019Microsoft — Office 2021Microsoft — Office 2024Microsoft — Office Online Server

CWE

Referencias

JSON original (NVD)

Mostrar
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