CVE-2026-8948

Estado: ModificadaCrítica (9.1)—

Same-origin policy bypass in the DOM: Networking component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Puntuación base: 9.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.45%
Percentil entre todas las CVEs puntuadas: 37
Fecha de la puntuación: 4/10/2026

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 access95 %
Impacto principalT1059.007 JavaScriptexecution85 %
Impacto secundarioT1005 Data from Local Systemcollection75 %

Vector CVSS con AV:N/PR:N/UI:N indica explotación remota sin privilegios (T1190). SOP bypass en DOM permite XSS (T1059.007) y acceso a datos del navegador (T1005).

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 Restrict Web-Based Content Privileged Account Management Network Segmentation Limit Access to Resource Over Network Filter Network Traffic

Tecnologías afectadas (2)

Mozilla — Firefox Mozilla — Thunderbird

CWE

CWE-942
CWE-79

Referencias

JSON original (NVD)

Mostrar

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