CVE-2026-53803

rsync before 3.5.0 contains a symlink following vulnerability that allows local attackers to overwrite arbitrary files by placing a symlink at a predictable output path such as --log-file, --write-batch, or daemon-mode log and statistics paths. Attackers can exploit rsync's failure to reject symlinks during ancillary file writes to redirect output to arbitrary filesystem locations, achieving local privilege escalation on installations where rsync runs with elevated privileges such as setuid or privileged daemon configurations.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/RsyncProject/rsync/releases/tag/v3.5.0	Product Release Notes
https://github.com/RsyncProject/rsync/security/advisories/GHSA-g9f4-7q66-9582	Vendor Advisory
https://www.vulncheck.com/advisories/rsync-symlink-following-arbitrary-file-overwrite	Release Notes Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*

History

23 Oct 2026, 18:10

Type	Values Removed	Values Added
Summary		(es) rsync anterior a la versión 3.5.0 contiene una vulnerabilidad de seguimiento de enlaces simbólicos que permite a atacantes locales sobrescribir archivos arbitrarios al colocar un enlace simbólico en una ruta de salida predecible como --log-file, --write-batch, o rutas de registro y estadísticas en modo demonio. Los atacantes pueden exploit el fallo de rsync al rechazar enlaces simbólicos durante escrituras de archivos auxiliares para redirigir la salida a ubicaciones arbitrarias del sistema de archivos, logrando escalada de privilegios local en instalaciones donde rsync se ejecuta con privilegios elevados como setuid o configuraciones de demonio privilegiado.

Information

Published : 2026-08-13 15:19

Updated : 2026-10-24 16:10

NVD link : CVE-2026-53803

Mitre link : CVE-2026-53803

CVE.ORG link : CVE-2026-53803

JSON object : View

Products Affected

samba

rsync

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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