CVE-2026-100784

Estado: AnalizadaAlta (8.8)—

Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Puntuación base: 8.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.32%
Percentil entre todas las CVEs puntuadas: 23
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.

ExplotaciónT1203 Exploitation for Client Executionexecution85 %
Impacto principalT1059 Command and Scripting Interpreterexecution75 %
Impacto secundarioT1565.001 Stored Data Manipulationimpact60 %

CVE-2026-100784 es un use-after-free (CWE-416) en Firefox que requiere interacción del usuario (UI:R) para ser explotado remotamente. El defecto en Layout: Text and Fonts permite ejecución de código tras manipular objetos de memoria.

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

Restrict Web-Based Content Restrict File and Directory Permissions Privileged Account Management Remote Data Storage Limit Software Installation Execution Prevention

Tecnologías afectadas (2)

Mozilla — Firefox Mozilla — Thunderbird

CWE

CWE-416

Referencias

JSON original (NVD)

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