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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).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

TOCTOU en daemon rsync con PR:L permite escalada de privilegios escribiendo archivos arbitrarios. Acceso local sin UI:R y capacidad de modificar/crear archivos confirma T1068 como explotación; T1565.001 (manipulación de datos) e impacto secundario de escalada al ejecutar con permisos elevados.

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 ProgramRestrict File and Directory PermissionsRemote Data StorageExecution PreventionEncrypt Sensitive InformationApplication Isolation and Sandboxing

Tecnologías afectadas (1)

Samba — Rsync

CWE

Referencias

JSON original (NVD)

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