The WP Bulk Delete plugin for WordPress is vulnerable to generic SQL Injection via the 'delete_user_roles' parameter in all versions up to, and including, 1.4.2 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for authenticated attackers, with administrator-level access and above, to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database. wp_unslash() is applied to the raw POST body before parse_str() decomposes it, stripping WordPress magic-quotes protection and leaving attacker-controlled values fully unescaped prior to reaching the SQL sink.