The click5 CRM add-on to Gravity Forms WordPress plugin through 1.0.3 does not have authorisation and CSRF checks when updating options via a REST endpoint, and does not ensure that the option to be updated belongs to the click5 CRM add-on to Gravity Forms WordPress plugin through 1.0.3. As a result, unauthenticated attackers could change arbitrary blog options, allowing them to create a new administrator account and take over the site.