Appointment Booking Plugin <= 5.7.0 - Unauthenticated Arbitrary Shortcode Execution via First/Last Name Field

The The Appointment Booking Plugin – LatePoint | Calendar & Scheduling for WordPress plugin for WordPress is vulnerable to arbitrary shortcode execution in all versions up to, and including, 5.7.0. This is due to the software allowing users to execute an action that does not properly validate a value before running do_shortcode. This makes it possible for unauthenticated attackers to execute arbitrary shortcodes. The payload is planted during the unauthenticated booking flow and triggered when the Customer Cabinet block rendered by render_customer_dashboard() outputs the stored name into the content stream, where WordPress core's do_shortcode filter at priority 11 re-parses and executes it.