The Unbounce Landing Pages WordPress plugin before 1.1.5 does not perform any authorisation check when updating the configuration its front-end proxy relies on, allowing any authenticated user, such as a subscriber, to point that proxy at a host they control and have arbitrary content served from the site's own origin.
https://wpscan.com/vulnerability/f13143dc-5674-4e9f-8aa0-8d22df7a7379/