CVE-2026-55055

Estado: AnalizadaAlta (7.8)—

Stack-based buffer overflow 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:R/S:U/C:H/I:H/A:H
Puntuación base: 7.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.57%
Percentil entre todas las CVEs puntuadas: 45
Fecha de la puntuación: 3/10/2026

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.

ExplotaciónT1203 Exploitation for Client Executionexecution95 %
Impacto principalT1059 Command and Scripting Interpreterexecution90 %
Impacto secundarioT1068 Exploitation for Privilege Escalationprivilege escalation75 %

AV:L + UI:R + buffer overflow (CWE-121) en Word indica ejecución en cliente al abrir archivo malicioso. CWE-121 + 'execute code' permite T1059; acceso local sin privilegios puede escalar a admin (T1068).

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 Application Isolation and Sandboxing Exploit Protection Update Software Threat Intelligence Program Restrict Web-Based Content

Tecnologías afectadas (7)

Microsoft — 365 Apps Microsoft — Microsoft 365 Microsoft — Office 2019 Microsoft — Office 2021 Microsoft — Office 2024 Microsoft — Sharepoint Server Microsoft — Word

CWE

CWE-121

Referencias

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55055

JSON original (NVD)

Mostrar

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