Vulnerability · Published Jun 26, 2026 · Assigned by GitHub_M
CVE-2026-55189RustFS: FTP frontend skips IAM authorization on object reads
High 7.7
In plain English
A high-severity missing authorization in rustfs from rustfs. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 28% of all known vulnerabilities).
Official 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.
Affected products (as reported)
Weakness: CWE-862, CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
References
- https://github.com/rustfs/rustfs/security/advisories/GHSA-3g29-xff2-92vp x_refsource_CONFIRM