The Redux Framework plugin for WordPress is vulnerable to Stored Cross-Site Scripting via theme_opts Parameter via User Profile in all versions up to, and including, 4.5.16 due to insufficient input sanitization and output escaping. 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. Successful exploitation requires the host theme to have registered a Redux field of a CSS-emitting type (such as link_color, border, or typography) with an output CSS selector, as only the field types 'spinner', 'slider', 'color', and 'date' receive per-type value validation that would block the entity-encoded payload.