The Click to Chat – WA Widget plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the [chat] shortcode 'num' parameter in all versions up to, and including, 4.38. This is due to insufficient escaping when embedding user-supplied shortcode attribute values inside JavaScript string literals that are then placed in HTML event-handler attributes. The CCW_Shortcode::shortcode() function applies esc_attr() to the 'num' parameter (line 157), which converts single quotes to the HTML entity '. This entity-encoded value is then interpolated directly into a JavaScript window.open() call string delimited by single quotes (line 194/221), and that complete string is placed verbatim into an HTML onclick attribute in the style template files (e.g., sc-style-1.php line 6). Because browsers HTML-decode event attribute values before executing the embedded JavaScript, the ' entities are decoded back to literal single quotes at runtime, allowing the injected payload to break o

The Click to Chat – WA Widget plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the [chat] shortcode 'num' parameter in all versions up to, and including, 4.38. This is due to insufficient escaping when embedding user-supplied shortcode attribute values inside JavaScript string literals that are then placed in HTML event-handler attributes. The CCW_Shortcode::shortcode() function applies esc_attr() to the 'num' parameter (line 157), which converts single quotes to the HTML entity '. This entity-encoded value is then interpolated directly into a JavaScript window.open() call string delimited by single quotes (line 194/221), and that complete string is placed verbatim into an HTML onclick attribute in the style template files (e.g., sc-style-1.php line 6). Because browsers HTML-decode event attribute values before executing the embedded JavaScript, the ' entities are decoded back to literal single quotes at runtime, allowing the injected payload to brea...