If you have a look at the top-right corner of https://jeremylong.github.io/DependencyCheck/dependency-check-gradle, you see that the "Fork me on GitHub" image is broken.

Navigating to the used URL https://s3.amazonaws.com/github/ribbons/forkme_right_gray_6d6d6d.png gives an "AccessDenied" response.