Service Finder Bookings <= 6.0 - Unauthenticated Privilege Escalation via claim_business

The Service Finder Bookings plugin for WordPress is vulnerable to privilege escalation via account takeover in all versions up to, and including, 6.0. This is due to the plugin not properly validating a user's identity prior to claiming a business when using the claim_business AJAX action. This makes it possible for unauthenticated attackers to login as any user including admins. Please note that subscriber privileges or brute-forcing are needed when completing the business takeover. The claim_id is needed to takeover the admin account, but brute-forcing is a practical approach to obtaining valid IDs.