GHSA-7gwp-5pfp-969j: MLflow: Unauthenticated full-read SSRF in webhook delivery: _validate_webhook_url bypassed via unvalidated HTTP redirects (and DNS rebinding)

MLflow's default Tracking Server has an unauthenticated SSRF (server-side request forgery, where an attacker tricks the server into making requests to internal systems) vulnerability in its webhook testing endpoint. The security check that validates webhook URLs can be bypassed because MLflow follows HTTP redirects without re-validating the redirect target, allowing an attacker to redirect from an allowed public server to internal/private addresses like metadata services.