CVE-2026-66141

Estado: AnalizadaAlta (7.8)—

Exim before 4.99.5 allows .forward privilege escalation because force_command for a pipe transport is 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: 0.14%
Percentil entre todas las CVEs puntuadas: 3
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.

ExplotaciónT1068 Exploitation for Privilege Escalationprivilege escalation95 %
Impacto principalT1059 Command and Scripting Interpreterexecution85 %
Impacto secundarioT1078 Valid Accountsstealth · persistence · privilege escalation · initial access75 %

AV:L + PR:L sin UI permite escalada local mediante .forward malformado en transporte pipe. Consigue ejecución de comandos (force_command) y acceso elevado (C:H I:H A: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

Privileged Account Management Execution Prevention Application Developer Guidance Active Directory Configuration User Training User Account Management

Tecnologías afectadas (1)

Exim — Exim

CWE

CWE-829

Referencias

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

JSON original (NVD)

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