CVE-2026-6758

Estado: AnalizadaAlta (7.5)—

Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Puntuación base: 7.5

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.50%
Percentil entre todas las CVEs puntuadas: 41
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 principalT1499.004 Application or System Exploitationimpact80 %

Use-after-free remoto sin autenticación (AV:N/PR:N) en WebAssembly de Firefox/Thunderbird permite crash DoS; explotación T1190 por acceso red sin privilegios, impacto T1499.004 (HTTP flood equivalente a agotamiento de aplicación).

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

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

Tecnologías afectadas (2)

Mozilla — Firefox Mozilla — Thunderbird

CWE

CWE-416

Referencias

JSON original (NVD)

Mostrar

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