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CVE-2026-55899

Estado: AnalizadaAlta (7.8)—

Stack-based buffer overflow 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.

Buffer overflow en Excel con UI:R (requiere abrir archivo) y acceso local. Ejecución de código confirmada. T1203 por interacción usuario; T1059 por ejecución de comandos derivada del overflow.

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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  "published": "2026-07-14T17:17:09.443",
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