Link following in Rsync - CVE-2026-53784
Published: August 13, 2026
Vulnerability identifier: #VU142295
CSH Severity: Low
CVSS v4: 8.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-53784
CWE-ID: CWE-59
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to disclose sensitive information and modify served content outside the configured module root.
The vulnerability exists due to improper link resolution before file access in the daemon module-root chdir logic when changing directory into the module path with use chroot = no. A local user can place a parent-component symlink to make the daemon serve files from outside the configured module root to disclose sensitive information and modify served content outside the configured module root.
Exploitation requires the daemon to be configured with use chroot = no, and the issue occurs before any transfer begins.
Affected software
Rsync
How to mitigate CVE-2026-53784
Install security update from vendor's website.
Rsync - update to 3.5.0