CVE-2026-55189

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 v3 7.7 HIGH

7.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.1 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/rustfs/rustfs/security/advisories/GHSA-3g29-xff2-92vp
https://github.com/rustfs/rustfs/security/advisories/GHSA-3g29-xff2-92vp

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-26 20:17

Updated : 2026-06-29 16:16

NVD link : CVE-2026-55189

Mitre link : CVE-2026-55189

CVE.ORG link : CVE-2026-55189

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

CWE-863

Incorrect Authorization

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