CVE-2026-21260

Estado: AnalizadaAlta (7.5)—

Exposure of sensitive information to an unauthorized actor 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: 1.51%
Percentil entre todas las CVEs puntuadas: 74
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 principalT1005 Data from Local Systemcollection80 %
Impacto secundarioT1566.002 Spearphishing Linkinitial access70 %

AV:N/PR:N/UI:N indica exposición en red sin autenticación (T1190). CWE-200 + descripción de información sensible expuesta permite T1005. El spoofing en Outlook sugiere también exfiltración de datos de correo (T1566.002 como impacto 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

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

Tecnologías afectadas (5)

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

CWE

CWE-200

Referencias

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21260

JSON original (NVD)

Mostrar

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