CVE-2026-20949
Estado: AnalizadaAlta (7.8)—
Improper access control in Microsoft Office Excel allows an unauthorized attacker to bypass a security feature 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: 0.47%
- Percentil entre todas las CVEs puntuadas: 39
- 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).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1203Exploitation for Client Executionexecution95 % - Impacto principal
T1078Valid Accountsstealth · persistence · privilege escalation · initial access75 % - Impacto secundario
T1552Unsecured Credentialscredential access70 %
Vector CVSS con AV:L y UI:R confirma T1203 (ejecución en cliente al abrir archivo). CWE-284 (improper access control) sugiere bypass de autenticación/autorización (T1078) y potencial acceso a datos sensibles (T1552) tras el bypass.
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 (2)
CWE
- CWE-284
Referencias
JSON original (NVD)
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