rclone is a command-line program to sync files and directories to and from different cloud storage providers. From 1.70.0 until 1.75.1, the serve/start RC interface accepts per-server proxyOpt.AuthProxy settings, and the FTP and S3 constructors in cmd/serve/ftp/ftp.go and cmd/serve/s3/server.go incorrectly check the process-global proxy.Opt.AuthProxy value instead. When the global value is empty, the request-local authentication proxy is ignored: FTP falls back to the fixed filesystem with username anonymous and any password, while S3 with AuthKey serves the fixed RC fs rather than the backend selected by the proxy. The dedicated command-line servers that configure the global option are not affected. This issue is fixed in version 1.75.1.
History

Thu, 10 Sep 2026 16:30:00 +0000

Type Values Removed Values Added
Description rclone is a command-line program to sync files and directories to and from different cloud storage providers. From 1.70.0 until 1.75.1, the serve/start RC interface accepts per-server proxyOpt.AuthProxy settings, and the FTP and S3 constructors in cmd/serve/ftp/ftp.go and cmd/serve/s3/server.go incorrectly check the process-global proxy.Opt.AuthProxy value instead. When the global value is empty, the request-local authentication proxy is ignored: FTP falls back to the fixed filesystem with username anonymous and any password, while S3 with AuthKey serves the fixed RC fs rather than the backend selected by the proxy. The dedicated command-line servers that configure the global option are not affected. This issue is fixed in version 1.75.1.
Title rclone: RC per-server auth-proxy bypass
Weaknesses CWE-863
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-09-10T16:08:14.619Z

Updated: 2026-09-10T17:14:40.559Z

Reserved: 2026-09-09T21:22:45.433Z

Link: CVE-2026-88044

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-10T17:17:08.387

Modified: 2026-09-10T17:17:08.387

Link: CVE-2026-88044

cve-icon Redhat

No data.