Gogs: Migration Redirect Bypass Leads to Internal Repository Theft

Gogs is an open source self-hosted Git service. Prior to 0.14.3, a Server-Side Request Forgery (SSRF) vulnerability exists in the repository migration functionality. The application validates only the initially submitted URL hostname, but git clone --mirror follows HTTP redirects. An authenticated user can submit a public URL that redirects to a blocked internal endpoint (e.g., 127.0.0.1), importing the internal repository's contents into an attacker-controlled repository. This vulnerability is fixed in 0.14.3.