Vulnerability Summary: Blind SSRF in Remote Schema Retrieval of API Tool Overview Title: Blind Server-Side Request Forgery (SSRF) in Remote Schema Retrieval of API Tool Description: A blind SSRF vulnerability exists in the method. This function directly uses to fetch the OpenAPI JSON schema from a user-provided URL, bypassing the internal protection mechanism. Impact: Allows authenticated users (even with low privileges) to induce the server to make arbitrary HTTP GET requests to internal network resources or cloud metadata services. Scope of Impact Ecosystem: PyPI / Docker Package Name: langgenius/dify Affected Versions: <= 0.6.9 (verified on commit ) Fixed Version: No specific version number provided Remediation Recommendation: Use to securely retrieve external resources instead of directly importing and using . Proof-of-Concept (PoC) Code Manual Reproduction (Curl) Observations If the internal port is open (e.g., Redis), the server will connect and receive data (even if it is not a valid JSON schema), returning a 400 error , confirming that the connection was established. If the internal port is closed, the server will return a error or timeout, which can be distinguished from the response of an open port.