The OTA Sync Booking Engine Widget plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 1.2.7. This is due to missing or incorrect nonce validation on the otasync_widget_settings_fnc() function. This makes it possible for unauthenticated attackers to update the plugin's settings and inject malicious scripts via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.