Affected: Bitnami: rclone

rclone is a command-line program to sync files and directories to and from different cloud storage providers. From v1.51.0 until v1.75.0, the local backend in backend/local/local.go relies on the configurable filename encoder to prevent remote filename data from becoming operating-system path syntax, so a local destination using Slash, None, Raw, or on Windows an encoding that preserves backslash can decode a standard-encoded fullwidth dot-dot component or native backslash form into an actual parent-directory component before filepath.Join resolves it outside the configured local root, allowing an attacker-controlled source object to create or overwrite files outside the selected destination directory as the rclone process. This issue is fixed in v1.75.0.

rclone is a command-line program to sync files and directories to and from different cloud storage providers. From v1.51.0 until v1.75.0, the local backend in backend/local/local.go relies on the configurable filename encoder to prevent remote filename data from becoming operating-system path syntax, so a local destination using Slash, None, Raw, or on Windows an encoding that preserves backslash can decode a standard-encoded fullwidth dot-dot component or native backslash form into an actual parent-directory component before filepath.Join resolves it outside the configured local root, allowing an attacker-controlled source object to create or overwrite files outside the selected destination directory as the rclone process. This issue is fixed in v1.75.0.

Affected: Go: github.com/rclone/rclone

## Summary

The local backend relies on its configurable filename encoder to prevent remote filename data from becoming operating-system path syntax. If a local destination uses an encoding that omits `Dot`, such as `Slash`, `None`, or `Raw`, a remote object's standard-encoded `．．` component is decoded into an actual `..` component. `backend/local.localPath` then passes the decoded name to `filepath.Join`, which resolves the component and produces a path outside the configured local root.

An attacker who can create object names in a remote source that a victim copies or synchronizes to such a local destination can create or overwrite files outside the selected destination directory, with the permissions of the rclone process.

The default local encoding includes `Dot` and is not affected by that exact path. This finding requires a non-default local encoding that preserves filesystem path syntax. On Windows, a second confirmed form uses a preserved backslash to turn a remote filename into a native `..\file` path even when the destination encoding still includes `Dot`.

This is not merely an odd filename-conversion result. The local remote's configured root is the destination selected by the user, and ordinary backend operations are expected to remain within it. Rclone documents custom and `Raw` encodings as filename-conversion controls; it does not document them as an opt-out from destination confinement. The defect is that confinement depends on an encoding mask instead of…

Affected: Ubuntu:18.04:LTS: rclone, Ubuntu:Pro:20.04:LTS: rclone, Ubuntu:Pro:22.04:LTS: rclone, Ubuntu:Pro:24.04:LTS: rclone, Ubuntu:Pro:26.04:LTS: rclone

rclone is a command-line program to sync files and directories to and from different cloud storage providers. From v1.51.0 until v1.75.0, the local backend in backend/local/local.go relies on the configurable filename encoder to prevent remote filename data from becoming operating-system path syntax, so a local destination using Slash, None, Raw, or on Windows an encoding that preserves backslash can decode a standard-encoded fullwidth dot-dot component or native backslash form into an actual parent-directory component before filepath.Join resolves it outside the configured local root, allowing an attacker-controlled source object to create or overwrite files outside the selected destination directory as the rclone process. This issue is fixed in v1.75.0.

Ein Angreifer kann mehrere Schwachstellen in rclone ausnutzen, um beliebigen Programmcode auszuführen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, und um Sicherheitsvorkehrungen zu umgehen.