Welcart e-Commerce <= 2.11.20 - Authenticated (Editor+) Stored Cross-Site Scripting

The Welcart e-Commerce plugin for WordPress is vulnerable to Stored Cross-Site Scripting via settings in all versions up to, and including, 2.11.20 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with editor-level permissions and above, 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.