2026-04-09 12:28:06
Wordfence
PUBLISHED
The Online Scheduling and Appointment Booking System – Bookly plugin for WordPress is vulnerable to price manipulation via the tips parameter in all versions up to, and including, 27.0. This is due to the plugin trusting a user-supplied input without server-side validation against the configured price. This makes it possible for unauthenticated attackers to submit a negative number to the tips parameter, causing the total price to be reduced to zero.