The Emailchef plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the page_options_ajax_disconnect() function in all versions up to, and including, 3.5.1. This makes it possible for authenticated attackers, with Subscriber-level access and above, to delete the plugin's settings via the 'emailchef_disconnect' AJAX action.
https://plugins.trac.wordpress.org/browser/emailchef/trunk/admin/class-emailchef-admin.php#L200
https://plugins.trac.wordpress.org/browser/emailchef/trunk/admin/class-emailchef-admin.php#L121
https://plugins.trac.wordpress.org/browser/emailchef/tags/3.5.1/admin/class-emailchef-admin.php#L200
https://plugins.trac.wordpress.org/browser/emailchef/tags/3.5.1/admin/class-emailchef-admin.php#L121