Open WebUI has SSRF in /openai/models

The /openai/models endpoint in open-webui/open-webui version 0.3.8 is vulnerable to Server-Side Request Forgery (SSRF). An attacker can change the OpenAI URL to any URL without checks, causing the endpoint to send a request to the specified URL and return the output. This vulnerability allows the attacker to access internal services and potentially gain command execution by accessing instance secrets.