CVE-2026-66140

Estado: AnalizadaAlta (7.8)—

Exim before 4.99.5 allows directory traversal to access files outside of the spool area, and consequently gain privileges, because arguments related to queue-name are mishandled.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 7.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.39%
Percentil entre todas las CVEs puntuadas: 30
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.

ExplotaciónT1068 Exploitation for Privilege Escalationprivilege escalation90 %
Impacto principalT1005 Data from Local Systemcollection85 %
Impacto secundarioT1548 Abuse Elevation Control Mechanismprivilege escalation80 %

Acceso local (AV:L) sin interacción (UI:N) permite escalada local mediante directory traversal en argumentos de queue-name de Exim, alcanzando confidencialidad e integridad altas (C:H/I:H).

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 Update Software User Account Management Threat Intelligence Program Restrict File and Directory Permissions Privileged Account Management

Tecnologías afectadas (1)

Exim — Exim

CWE

CWE-24

Referencias

https://openwall.com/lists/oss-security/2026/07/22/9

JSON original (NVD)

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