CVE-2026-21511

Estado: AnalizadaAlta (7.5)—

Deserialization of untrusted data in Microsoft Office Outlook allows an unauthorized attacker to perform spoofing over a network.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Puntuación base: 7.5

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 3.85%
Percentil entre todas las CVEs puntuadas: 90
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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access85 %
Impacto principalT1566.001 Spearphishing Attachmentinitial access75 %
Impacto secundarioT1187 Forced Authenticationcredential access70 %

Vector CVSS AV:N/AC:L/PR:N/UI:N indica explotación remota sin privilegios (T1190). CWE-502 (deserialización) y "spoofing" en Outlook sugieren phishing/suplantación de identidad (T1566.001) como impacto primario; T1187 (Domain Spoofing) secundario.

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

Filter Network Traffic Vulnerability Scanning User Training User Account Management Restrict Web-Based Content Privileged Account Management

Tecnologías afectadas (5)

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

CWE

CWE-502

Referencias

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21511

JSON original (NVD)

Mostrar

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