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CVE-2026-84642

Estado: AnalizadaAlta (7.5)—

The values of the mail.allowed_attachment_hostnames advanced config setting were used in a regular expression without escaping. For some possible valid hostnames, this could allow certain unintended hostnames to also match and serve remote attachments. This vulnerability was fixed in Thunderbird 155 and Thunderbird 153.2.

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.

AV:N sin autenticación ni interacción = T1190. Acceso a archivos adjuntos remotos no autorizados (C:H) = T1005. Distribución de adjuntos maliciosos = T1566.002.

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 ScanningUser TrainingUser Account ManagementRestrict Web-Based ContentPrivileged Account ManagementNetwork Segmentation

Tecnologías afectadas (1)

Mozilla — Thunderbird

CWE

Referencias

JSON original (NVD)

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