See how paymattic compares to other vendors in security performance
The Simple Payment Donations & Subscriptions WordPress plugin before 4.2.1 does not sanitise and escape user input given in its forms, which could allow unauthenticated attackers to perform Cross-Site Scripting attacks against admins
The Paymattic WordPress plugin from 4.6.20 before 4.6.26 does not verify that a confirmed Stripe payment belongs to the order it is applied to, allowing unauthenticated users to mark an arbitrary pending order as paid by confirming a smaller payment of their own against it.