SiYuan is a personal knowledge management system. Prior to 3.6.0, the /api/network/forwardProxy endpoint allows authenticated users to make arbitrary HTTP requests from the server. The endpoint accepts a user-controlled URL and makes HTTP requests to it, returning the full response body and headers. There is no URL validation to prevent requests to internal networks, localhost, or cloud metadata services. This vulnerability is fixed in 3.6.0.
CWE-918