CVE-2026-3888

Estado: AnalizadaAlta (7.8)—

Local privilege escalation in snapd on Linux allows local attackers to get root privilege by re-creating snap's private /tmp directory when systemd-tmpfiles is configured to automatically clean up this directory. This issue affects Ubuntu 16.04 LTS, 18.04 LTS, 20.04 LTS, 22.04 LTS, and 24.04 LTS.

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: 0.18%
Percentil entre todas las CVEs puntuadas: 7
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 principalT1548.004 Elevated Execution with Promptprivilege escalation90 %
Impacto secundarioT1543.002 Systemd Servicepersistence · privilege escalation75 %

Escalada local de privilegios (AV:L, PR:L) en snapd explotando race condition con systemd-tmpfiles para obtener acceso root. Impactos: abuso de mecanismos de elevación (T1548.004) y manipulación de servicios del sistema (T1543.002).

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

Tecnologías afectadas (1)

Canonical — Ubuntu Linux

CWE

CWE-268

Referencias

JSON original (NVD)

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