The Pinpoint Booking System WordPress plugin before 2.9.9.4.8 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup)
https://wpscan.com/vulnerability/bab46c28-71aa-4610-9683-361e7b008d37/