The OpenPOS Lite – Point of Sale for WooCommerce plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'width' parameter of the order_qrcode shortcode in all versions up to, and including, 3.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.