AutoBangumi before 3.2.8 contains a server-side request forgery (SSRF) vulnerability that allows unauthenticated remote attackers to probe internal network services by supplying arbitrary host values to an unprotected setup endpoint. Attackers can send requests to the POST /api/v1/setup/test-downloader endpoint during the initial setup window, causing the server to issue HTTP GET requests to internal or reserved addresses and leak information through echoed connection-error messages.