# CVE-2026-71311: rclone CRLF injection in FTP backend via custom filename encoding

Source: https://junglewise.ai/threats/cve-2026-71311-rclone-crlf-injection-in-ftp-backend-via-custom-filename-encoding  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-05. Updated: 2026-08-05  
License: CC BY 4.0 with a link back

CVE-2026-71311 · Severity: medium · CVSS 6.4 · Published 2026-08-05

rclone is a command-line program used to manage and sync files between different cloud storage providers and file servers. A vulnerability in its FTP backend allows an attacker to inject unauthorized commands by using specially crafted filenames containing newlines. If a user syncs files from a malicious source to an FTP server using a non-standard configuration, the attacker could delete files or perform other unauthorized actions on the destination server.

Technologies: [github.com/rclone/rclone (Go)](https://junglewise.ai/threats/technologies/github-com-rclone-rclone), [Rclone](https://junglewise.ai/threats/technologies/rclone). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [Rclone](https://junglewise.ai/threats/vendors/rclone).

## Quick answers

**Is CVE-2026-71311 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-71311 being exploited in the wild.

**How severe is CVE-2026-71311?** Medium severity, with a CVSS score of 6.4, published 5 August 2026.

**Which products and versions are affected?** github.com/rclone/rclone (Go) < 1.75.0, SEMVER:introduced=0,fixed=1.75.0; Rclone < 1.75.0.

**Is there a fix for CVE-2026-71311?** Yes. github.com/rclone/rclone (Go): upgrade to 1.75.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-71311 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-71311?** Check whether you run github.com/rclone/rclone (Go) or Rclone at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/rclone/rclone (Go): upgrade to 1.75.0 or later

  ```sh
  go get github.com/rclone/rclone@v1.75.0
  ```


## Technical details

A CRLF injection vulnerability exists in rclone's FTP backend when using custom filename encodings that do not mask control characters. The root cause is that rclone's 'FromStandardPath' function can restore raw CR/LF characters from internal representations before they are passed to the underlying FTP library. Because the 'github.com/jlaffaye/ftp' dependency does not validate command arguments for newlines, these characters allow an attacker to terminate the intended FTP command and start a new, arbitrary command (such as DELE). Exploitation requires the attacker to be able to create files in a source namespace that is subsequently synced to an FTP destination by a victim using a vulnerable encoding configuration. The vulnerability was patched in version 1.75.0 by implementing stricter argument validation.

## Affected products

- rclone rclone < 1.75.0

## Identifiers

- CVE-2026-71311
- GHSA-8c48-q9wj-3w37
- GO-2026-6187

## Timeline

- 2026-07-31: patched: Fix released in version 1.75.0
- 2026-08-05: disclosed: Public advisory published

## References

- [https://api.github.com/users/cyberlanc3r](https://api.github.com/users/cyberlanc3r)
- [https://github.com/cyberlanc3r](https://github.com/cyberlanc3r)
- [https://api.github.com/users/cyberlanc3r/gists%7B/gist_id%7D](https://api.github.com/users/cyberlanc3r/gists%7B/gist_id%7D)
- [https://api.github.com/users/cyberlanc3r/repos](https://api.github.com/users/cyberlanc3r/repos)
- [https://avatars.githubusercontent.com/u/216992819?v=4](https://avatars.githubusercontent.com/u/216992819?v=4)
- [https://api.github.com/users/cyberlanc3r/events%7B/privacy%7D](https://api.github.com/users/cyberlanc3r/events%7B/privacy%7D)

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