The WPC Smart Compare for WooCommerce plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'shortcode_btn' shortcode in all versions up to, and including, 6.4.6 due to insufficient input sanitization and output escaping on user supplied attributes. 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.
https://plugins.trac.wordpress.org/browser/woo-smart-compare/tags/6.4.5/wpc-smart-compare.php#L2616
https://plugins.trac.wordpress.org/browser/woo-smart-compare/tags/6.4.5/wpc-smart-compare.php#L187