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CVE-2026-76642

Estado: Pendiente de análisisAlta (8.5)—

util-linux versions through 2.41.5 and 2.42.2 fail to check mount helper exit status before running post-mount hooks, allowing unprivileged users to execute privileged operations on pre-existing filesystems. Attackers can exploit X-mount.idmap or X-mount.owner hooks to clone filesystems with inherited suid bits or modify target inode permissions after a helper fails, achieving privilege escalation.

CVSS

Probabilidad de explotación (EPSS)

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.

AV:L, PR:L sin UI permitió a usuarios sin privilegios explotar fallos en validación de helpers de montaje para ejecutar operaciones privilegiadas y escalar privilegios mediante hooks post-montaje (X-mount.idmap, X-mount.owner).

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

User Account ManagementRestrict File and Directory PermissionsPrivileged Account ManagementOperating System ConfigurationExecution PreventionAudit

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Util-linux — Util-linuxAI

CWE

Referencias

JSON original (NVD)

Mostrar
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      "value": "util-linux versions through 2.41.5 and 2.42.2 fail to check mount helper exit status before running post-mount hooks, allowing unprivileged users to execute privileged operations on pre-existing filesystems. Attackers can exploit X-mount.idmap or X-mount.owner hooks to clone filesystems with inherited suid bits or modify target inode permissions after a helper fails, achieving privilege escalation."
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  "lastModified": "2026-09-24T20:28:01.780",
  "sourceIdentifier": "disclosure@vulncheck.com"
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