CVE-2026-35368

Estado: AnalizadaAlta (7.8)—

A vulnerability exists in the chroot utility of uutils coreutils when using the --userspec option. The utility resolves the user specification via getpwnam() after entering the chroot but before dropping root privileges. On glibc-based systems, this can trigger the Name Service Switch (NSS) to load shared libraries (e.g., libnss_*.so.2) from the new root directory. If the NEWROOT is writable by an attacker, they can inject a malicious NSS module to execute arbitrary code as root, facilitating a full container escape or privilege escalation.

CVSS

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

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.15%
Percentil entre todas las CVEs puntuadas: 3
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 escalation95 %
Impacto principalT1574.007 Path Interception by PATH Environment Variablestealth · execution90 %
Impacto secundarioT1548 Abuse Elevation Control Mechanismprivilege escalation85 %

Acceso local (AV:L) sin interacción en utilidad chroot; escalación por inyección de módulo NSS malicioso (CWE-426: Untrusted Search Path). Impactos: secuestro de librería dinámica (T1574.007) y ejecución como root (T1548).

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

Tecnologías afectadas (1)

Uutils — Coreutils

CWE

CWE-426

Referencias

JSON original (NVD)

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