The Tune Library plugin for WordPress is vulnerable to Stored Cross-Site Scripting via CSV import in all versions up to, and including, 1.6.3. This is due to insufficient input sanitization and output escaping on user supplied attributes. 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 the injected page. The vulnerability exists because the CSV import functionality lacks authorization checks and doesn't sanitize imported data, which is later rendered without escaping through the [tune-library] shortcode.