CVE-2026-71311 rclone CVE debrief

Who should care

Defenders responsible for managing rclone installations, especially in environments where FTP is used, should assess exposure and prioritize updating to version 1.75.0. This includes administrators and security teams overseeing cloud storage syncing operations.

Why it matters

CVE-2026-71311 is a medium-severity vulnerability in rclone that allows for command injection via malicious FTP filenames. Defenders should verify their rclone versions, especially in FTP-using environments, and update to version 1.75.0 if necessary. The vulnerability's impact is limited to the FTP protocol and requires specific conditions to be exploited.

• Potential for unauthorized FTP commands to be executed
• Possible disruption of FTP operations or data integrity
• Need for verification of rclone versions and FTP configurations
• Priority for updating to version 1.75.0 in vulnerable environments

Technical summary

The rclone program, used for syncing files and directories with cloud storage providers, has a vulnerability that allows an attacker to inject an independent authenticated FTP command. This occurs when a victim copies or syncs to a more-privileged FTP destination using a malicious FTP filename. The issue arises from improper handling of FTP filenames in the rclone backend, specifically in the ftp.go file. The vulnerability is fixed in version 1.75.0.

Defensive priority

Defenders should prioritize verifying their rclone versions and updating to 1.75.0 if necessary, especially in environments where rclone is used with FTP.

Recommended defensive actions

• Verify rclone version and update to 1.75.0 if necessary
• Review FTP usage and configurations in the environment
• Monitor for suspicious FTP activity
• Perform an inventory of assets using rclone with FTP
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Track exceptions and retest remediated assets
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed

Evidence notes

The vulnerability exists due to improper handling of FTP filenames in the rclone backend. An attacker can craft a malicious filename to inject an additional FTP command. This issue requires verification of rclone versions and FTP usage in the environment.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.