RSVPMaker < 7.8.2 - Unauthenticated SQL Injection

The plugin does not sanitise user input before using it in a SQL statement in the signedupajax AJAX action. Note: Even though the reported SQL Injection was fixed in v7.8.2, other additional sanitisation was implemented in v7.8.3 to 7.8.6. sqlmap -u "https://localhost/?action=signedup&eventcount=...