A Server-Side Request Forgery (SSRF) vulnerability exists in the gradio-app/gradio version 4.21.0, specifically within the /queue/join endpoint and the save_url_to_cache function. The vulnerability arises when the path value, obtained from the user and expected to be a URL, is used to make an HTTP request without sufficient validation checks. This flaw allows an attacker to send crafted requests that could lead to unauthorized access to the local network or the AWS metadata endpoint, thereby compromising the security of internal servers.