Contest Gallery <= 30.0.6 - Authenticated (Author+) Second-Order SQL Injection via MultipleFiles Second-Order Payload via 'cg_multiple_files_for_post' -> 'cgRealId'

The Contest Gallery – Upload & Vote Photos, Media, Sell with PayPal & Stripe plugin for WordPress is vulnerable to Second-Order SQL Injection via MultipleFiles Second-Order Payload via 'cg_multiple_files_for_post' -> 'cgRealId' in all versions up to, and including, 30.0.7 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 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.