The HTTP client in Gradle before 5.6 sends authentication credentials originally destined for the configured host. If that host returns a 30x redirect, Gradle also sends those credentials to all subsequent hosts that the request redirects to. This is similar to CVE-2018-1000007.
Gradle versions from 1.4 to 5.3.1 use an insecure HTTP URL to download dependencies when the built-in JavaScript or CoffeeScript Gradle plugins are used. Dependency artifacts could have been maliciously compromised by a MITM attack against the ajax.googleapis.com web site.