Technical impact
The vulnerability in rclone serving restic with the --private-repos flag allows an authenticated user to manipulate the URL path and include path traversal sequences such as ..\nThis bypasses the server’s authorization checks that rely on the routed user segment. As a result, the attacker can read, overwrite, or delete private repositories that belong to other users. The weakness originates from CWE‑22 (Path Traversal) and CWE‑639 (Privilege‑Escalation via Resource Control).
Affected Systems
All installations of rclone older than version 1.74.4 that use the serve restic --private-repos feature are affected. This includes any environment in which rclone is used to expose Restic repositories over HTTP or other network protocols, and where the underlying cloud backend sanitizes path components. The vulnerability is present in any rclone release prior to v1.74.4.
Risk and Exploitability
The CVSS score of 8.8 indicates a high severity vulnerability that impacts confidentiality, integrity, and availability. The EPSS score of fewer than 1 % suggests a low probability of current exploitation, and the issue is not listed in the CISA KEV catalog. However, an attacker can reach other users’ repositories. If the restic service is exposed to external networks, the path traversal can be triggered over standard network traffic, making the attack practical in many scenarios.
Github GHSA