CVE-2026-53793

A flaw was found in rsync. This vulnerability allows remote clients to bypass path confinement, a security measure designed to restrict file access. By crafting specific paths that include a '/./' boundary marker within a chroot environment, an attacker can gain unauthorized read or write access to files outside the intended module's directory. This could lead to sensitive information disclosure or data manipulation.

This Important rsync flaw enables remote clients to bypass path confinement when the daemon operates in chroot mode with a module root containing a /./ boundary marker. Successful exploitation could lead to unauthorized read and write access to files outside the intended chroot environment, though the attack complexity is high.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this issue, avoid configuring rsync modules with a /./ boundary marker in their root path when operating in chroot mode. Review existing rsync configurations to ensure that module root paths do not contain /./ when chroot is enabled. If chroot mode is not strictly required for a given rsync module, consider disabling it. If changes are made to the rsync configuration, a restart of the rsync service may be required for the changes to take effect.