The Contest Gallery Pro WordPress plugin before 19.1.5 does not escape the wp_user_id GET parameter before concatenating it to an SQL query in management-show-user.php. This may allow malicious users with at administrator privileges (i.e. on multisite WordPress configurations) to leak sensitive information from the site's database.
https://wpscan.com/vulnerability/dac32ed4-d3df-420a-a2eb-9e7d2435826a