CVE-2020-6819

Estado: AnalizadaAlta (8.1)⚠ Explotación activa

Under certain conditions, when running the nsDocShell destructor, a race condition can cause a use-after-free. We are aware of targeted attacks in the wild abusing this flaw. This vulnerability affects Thunderbird < 68.7.0, Firefox < 74.0.1, and Firefox ESR < 68.6.1.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 8.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 3.04%
Percentil entre todas las CVEs puntuadas: 87
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).

CISA KEV — explotada activamente

Añadida al catálogo: 3/11/2021
Plazo de remediación: 3/5/2022
Uso conocido en ransomware: Unknown

🎯 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 principalT1059 Command and Scripting Interpreterexecution80 %
Impacto secundarioT1068 Exploitation for Privilege Escalationprivilege escalation75 %

Race condition en destructor de nsDocShell (CWE-362, CWE-416) en navegadores Mozilla permite ejecución remota sin autenticación ni interacción. Explotación activa confirmada.

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 (2)

Mozilla — Firefox Mozilla — Thunderbird

CWE

CWE-362, CWE-416
CWE-416

Referencias

JSON original (NVD)

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