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CVE-2026-84637

Estado: AnalizadaCrítica (9.8)—

Malicious calendar invitations could use file URI attachments to launch local or network-hosted executables on Windows, bypassing Thunderbird's normal executable attachment protections. With the new invitation display enabled, the attachment could also appear under a misleading filename. This vulnerability was fixed in Thunderbird 154 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.

Invitaciones de calendario maliciosas con adjuntos file:// permiten ejecutar ejecutables locales/red, bypasando protecciones (AV:N/AC:L/PR:N/UI:N = T1190). Impacto: ejecución de código (T1059) + phishing con adjunto (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

Privileged Account ManagementVulnerability ScanningRestrict Web-Based ContentNetwork SegmentationLimit Software InstallationLimit Access to Resource Over Network

Tecnologías afectadas (1)

Mozilla — Thunderbird

CWE

Referencias

JSON original (NVD)

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