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CVE-2026-70626

Estado: AnalizadaAlta (8.6)—

NLTK versions before 3.9.4 contain a symlink escape vulnerability in CorpusReader.open() that allows local attackers to read arbitrary files outside the corpus root. The vulnerability exists because path validation is lexical and does not account for symlink resolution, enabling attackers to place symlinks inside the corpus root to access files outside the intended boundary.

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 local (AV:L) sin interacción que permite acceso no autorizado a archivos fuera del límite previsto mediante symlinks; escalada efectiva de permisos desde la aplicación NLTK hacia datos del sistema.

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

Update SoftwareActive Directory ConfigurationUser TrainingThreat Intelligence ProgramRestrict File and Directory PermissionsPrivileged Account Management

Tecnologías afectadas (1)

Nltk — Nltk

CWE

Referencias

JSON original (NVD)

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