Shiny Buttons <= 1.1.0 - Unauthenticated Stored Cross-Site Scripting

The Shiny Buttons WordPress plugin through 1.1.0 does not have any authorisation and CSRF in place when saving a template (wpbtn_save_template function hooked to the init action), nor sanitise and escape them before outputting them in the admin dashboard, which allow unauthenticated users to add a malicious template and lead to Stored Cross-Site Scripting issues.