The Simple Banner – Easily add multiple Banners/Bars/Notifications/Announcements to the top or bottom of your website plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'pro_version_activation_code' parameter in all versions up to, and including, 3.0.10 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.
CWE-79