CVE-2026-4702

Estado: ModificadaCrítica (9.8)—

JIT miscompilation in the JavaScript Engine component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 9.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.67%
Percentil entre todas las CVEs puntuadas: 50
Fecha de la puntuación: 5/10/2026

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 Command and Scripting Interpreterexecution90 %
Impacto secundarioT1068 Exploitation for Privilege Escalationprivilege escalation75 %

Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N indica explotación remota sin privilegios ni interacción: T1190. JIT miscompilation en motor JavaScript permite ejecución de código arbitrario (T1059) y potencialmente escalada de privilegios (T1068) desde el contexto del navegador.

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 Management Execution Prevention Application Isolation and Sandboxing Exploit Protection Update Software Vulnerability Scanning

Tecnologías afectadas (1)

Mozilla — Firefox

CWE

CWE-843
CWE-843

Referencias

JSON original (NVD)

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