The Contest Gallery WordPress plugin before 19.1.5.1, Contest Gallery Pro WordPress plugin before 19.1.5.1 do not escape the cg_copy_start POST parameter before concatenating it to an SQL query in copy-gallery-images.php. This may allow malicious users with at least author privilege to leak sensitive information from the site's database.
https://wpscan.com/vulnerability/a66af8f7-1d5f-4fe5-a2ba-03337064583b