Inurl Index.php%3fid= !!link!!

The search query inurl:index.php%3Fid= is a classic Google dork used for penetration testing and security research. It specifically looks for URLs containing index.php?id= (where %3F is the URL-encoded representation of ?).

Why use %3F instead of ??
Google may misinterpret ? as a search operator or ignore it. Encoding it ensures the literal ? is included in the search. inurl index.php%3Fid=

For outdated CMS:

inurl:index.php%3Fid= intext:"Powered by phpBB" | "Joomla" | "WordPress"

Limit Database Privileges: Make sure the database user account used by your web application has only the necessary privileges to perform its tasks, reducing the impact of a successful attack. The search query inurl:index