The Event Tickets with Ticket Scanner plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'data' parameters in all versions up to, and including, 2.4.4 due to insufficient input sanitization and output escaping and missing authorization on the functionality to manage tickets. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This missing authorization aspect of this was patched in 2.4.1, while the Cross-Site Scripting was fully patched in 2.4.4.