CVE-2026-74958

Estado: AnalizadaAlta (7.5)—

Information disclosure in the WebRTC component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

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: 0.45%
Percentil entre todas las CVEs puntuadas: 37
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 %

Vector CVSS AV:N/AC:L/PR:N/UI:N indica explotación remota sin autenticación (T1190). CWE-1021 y descripción de divulgación de información en WebRTC confirman acceso a datos locales (T1005) sin ejecución de código.

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 Privileged Account Management Network Segmentation Limit Access to Resource Over Network Filter Network Traffic Application Isolation and Sandboxing

Tecnologías afectadas (2)

Mozilla — Firefox Mozilla — Thunderbird

CWE

CWE-1021

Referencias

JSON original (NVD)

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