CVE-2026-42511

Estado: ModificadaAlta (8.1)—

The BOOTP file field is written to the lease file without escaping embedded double-quotes, allowing injection of arbitrary dhclient.conf directives. When the lease file is subsequently re-parsed by dhclient, e.g., after a system restart, an attacker-controlled field from the lease is passed to dhclient-script(8), which evaluates it.

A rogue DHCP server may be able to execute arbirary code as root on a system running dhclient.

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: 0.40%
Percentil entre todas las CVEs puntuadas: 32
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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access75 %
Impacto principalT1059 Command and Scripting Interpreterexecution85 %
Impacto secundarioT1068 Exploitation for Privilege Escalationprivilege escalation80 %

Vulnerabilidad en dhclient (servicio de red remoto) explotable sin autenticación desde red (AV:N, PR:N); inyección de directivas en fichero de configuración que permite ejecución arbitraria de código como root. CWE-149 (improper neutralization) y contexto de servidor DHCP rogue confirman T1190 + T10

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 (1)

Freebsd — Freebsd

CWE

CWE-149

Referencias

https://security.freebsd.org/advisories/FreeBSD-SA-26:12.dhclient.asc

JSON original (NVD)

Mostrar

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