GHSA-v9fg-3cr2-277j

Summary

A Stored Cross-Site Scripting (XSS) vulnerability in the RustFS Console allows an attacker to execute arbitrary JavaScript in the context of the management console. By bypassing the PDF preview logic, an attacker can steal administrator credentials from localStorage, leading to full account takeover and system compromise.

Details

The vulnerability exists due to improper validation of the response content type during the file preview process and a lack of origin separation between the S3 object delivery and the management console.

1. Origin of Credentials: The RustFS Console stores highly sensitive S3 credentials (AccessKey, SecretKey, SessionToken) in the browser's localStorage.
   • File: console/composables/useAuth.ts
   • Evidence: Lines 14 and 18-25 show that credentials are held in useLocalStorage('auth.credentials', {}) and useLocalStorage('auth.permanent', undefined).
2. Insecure Preview Implementation: In console/components/object/preview-modal.vue, the application identifies a PDF file based on its extension or metadata and renders it using an <iframe>.
3. Same-Origin Vulnerability: RustFS typically hosts the management console and the S3 API on the same origin (e.g., the same IP and port).
4. Bypass Attack: An attacker can upload a file named xss.pdf but set its Content-Type metadata to text/html. Because the iframe is hosted on the same origin as the console, the executed script has unrestricted access to the parent window's localStorage.

PoC

<img width="6006" height="3096" alt="CleanShot 2026-02-01 at 18 36 54@2x"...