Vulnerability Description
RustFS is a distributed object storage system built in Rust. From 1.0.0-alpha.1 until 1.0.0-beta.9, when the FTP frontend is enabled, the FTP read and probe handlers dispatch directly to the storage backend without ever calling the IAM authorization function that the FTP write/list handlers (and the entire HTTP S3 path) use. As a result, any user who can authenticate to the FTP listener — including a user whose IAM policy contains an explicit Deny on s3:GetObject — can read (RETR) and stat (SIZE/MDTM) any object in any bucket, and probe any bucket (CWD), completely regardless of their IAM policy. This vulnerability is fixed in 1.0.0-beta.9.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
FAQ
What is CVE-2026-55189?
CVE-2026-55189 is a vulnerability with a CVSS score of 7.7 (HIGH). RustFS is a distributed object storage system built in Rust. From 1.0.0-alpha.1 until 1.0.0-beta.9, when the FTP frontend is enabled, the FTP read and probe handlers dispatch directly to the storage b...
How severe is CVE-2026-55189?
CVE-2026-55189 has been rated HIGH with a CVSS base score of 7.7/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-55189?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.