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CVE-2026-29518

Estado: ModificadaAlta (7.3)—

Rsync versions before 3.4.3 contain a time-of-check to time-of-use (TOCTOU) race condition in daemon file handling that allows attackers to redirect file writes outside intended directories by replacing parent directory components with symbolic links. Attackers with write access to a module path can exploit this race condition to create or overwrite arbitrary files, potentially modifying sensitive system files and achieving privilege escalation when the daemon runs with elevated privileges. This vulnerability can only be triggered if the chroot setting is false.

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).

Tecnologías afectadas (1)

Samba — Rsync

CWE

Referencias

JSON original (NVD)

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      "lang": "en",
      "value": "Rsync versions before 3.4.3 contain a time-of-check to time-of-use (TOCTOU) race condition in daemon file handling that allows attackers to redirect file writes outside intended directories by replacing parent directory components with symbolic links. Attackers with write access to a module path can exploit this race condition to create or overwrite arbitrary files, potentially modifying sensitive system files and achieving privilege escalation when the daemon runs with elevated privileges. This vulnerability can only be triggered if the chroot setting is false."
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      "value": "Las versiones de Rsync anteriores a la 3.4.3 contienen una condición de carrera de tiempo de verificación a tiempo de uso (TOCTOU) en el manejo de archivos del demonio que permite a los atacantes redirigir escrituras de archivos fuera de los directorios previstos reemplazando componentes de directorios padre con enlaces simbólicos. Los atacantes con acceso de escritura a una ruta de módulo pueden explotar esta condición de carrera para crear o sobrescribir archivos arbitrarios, modificando potencialmente archivos sensibles del sistema y logrando la escalada de privilegios cuando el demonio se ejecuta con privilegios elevados. Esta vulnerabilidad solo puede activarse si la configuración de chroot es falsa."
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  "lastModified": "2026-08-19T12:17:41.960",
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