Attackers use this query to target directories that might contain sensitive "new" password lists, configuration files, or database backups that have been accidentally left public. The Security Risk of Directory Indexing
How To Disable Directory Listing on Your Web Server - Invicti
The search term refers to a specific technique used in "Google Dorking" to find exposed files on misconfigured web servers. When a web server does not have a default index page (like index.html ), it may display a list of all files in that directory—a feature known as directory indexing.
