The Welcart e-Commerce plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'customorder' parameter in all versions up to, and including, 2.12.1 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The injected payload is delivered via the guest checkout form, requiring no authentication, and executes when an administrator views the affected order in the WordPress admin panel.

The Welcart e-Commerce plugin for WordPress is vulnerable to SQL Injection via the cookie in all versions up to, and including, 2.11.21 due to insufficient escaping on the user supplied value and lack of sufficient preparation on the existing SQL query. This makes it possible for authenticated attackers, with Author-level access and above, to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database.