The search query is a Google hacking syntax (or "Google dork") used to locate unsecured, internet-connected security cameras that expose their live video feeds to the public.
The main.cgi file is a Common Gateway Interface script used by older network cameras (such as early Panasonic models) to stream live video or host the camera's primary control panel. When you combine these two operators, the search engine acts as an accidental directory for live, publicly accessible security cameras. Why Are These Cameras Exposed? intitle network camera inurl maincgi work
Manufacturers release updates to patch security holes. Ensure your camera is running the latest software. The search query is a Google hacking syntax