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CVE-2026-84140

Estado: ModificadaCrítica (9.8)—

Site isolation issue in the DOM: Navigation component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, 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.

Vulnerabilidad remota en DOM de navegador sin autenticación (AV:N PR:N UI:N). Site isolation bypass permite manipular datos, leer contenido de otras pestañas y secuestrar sesiones; vector CVSS indica C:H I:H A:H.

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 ScanningRestrict File and Directory PermissionsPrivileged Account ManagementRemote Data StorageNetwork SegmentationLimit Access to Resource Over Network

Tecnologías afectadas (2)

Mozilla — FirefoxMozilla — Thunderbird

CWE

Referencias

JSON original (NVD)

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