CVE-2026-84144

Estado: AnalizadaAlta (7.5)—

Internally found bugs present in Thunderbird 154 and Thunderbird ESR 153.1. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.

CVSS

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

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.43%
Percentil entre todas las CVEs puntuadas: 35
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 secundarioT1068 Exploitation for Privilege Escalationprivilege escalation65 %

Vector CVSS con UI:R (interacción del usuario) indica ejecución en cliente; corrupción de memoria en navegador/cliente de correo permite RCE o escalada de privilegios.

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

Execution Prevention Application Isolation and Sandboxing Exploit Protection Update Software Threat Intelligence Program Restrict Web-Based Content

Tecnologías afectadas (2)

Mozilla — Firefox Mozilla — Thunderbird

CWE

CWE-119

Referencias

JSON original (NVD)

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