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CVE-2026-66897

Estado: AnalizadaCrítica (9.9)—

A path traversal vulnerability in LXD's instance template processing allows an attacker with container edit permissions, or any user launching a crafted image, to overwrite arbitrary files on the host system as root. When processing target template paths specified in metadata.yaml, LXD validates the path against a confined os.Root directory handle but subsequently opens and creates the file using os.Create with an unconfined string path. This discrepancy between path resolution checks and file creation allows an attacker to escape directory confinement, overwrite root-owned host files, and achieve host root code execution.

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.

Vulnerabilidad de path traversal (CWE-22/23) en LXD que requiere PR:L pero acceso de red (AV:N) para explotar servicios remotos. El atacante sobrescribe ficheros del host como root, permitiendo ejecución de código remota.

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

Threat Intelligence ProgramPrivileged Account ManagementExecution PreventionDisable or Remove Feature or ProgramApplication Isolation and SandboxingExploit Protection

Tecnologías afectadas (1)

Canonical — LXD

CWE

Referencias

JSON original (NVD)

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