Lets put it this way: There are criminals that use whatsup, twitter, and the like for communication. They don't really last for some reason. Then there are those who use a special, commercial system. They might fail if they fall for traps like EncroChat (or however that was spelled). Then there are those who try to set up their own system, but lack the capabilities and talent for that. And last but not least are those groups you have not heard from in the news. They do have proper infosec.
Another way to stay under the radar. IIRC there was a case where information was passed on an image board by means of using random-looking filenames that actually encoded messages.
Lets put it this way: There are criminals that use whatsup, twitter, and the like for communication. They don't really last for some reason. Then there are those who use a special, commercial system. They might fail if they fall for traps like EncroChat (or however that was spelled). Then there are those who try to set up their own system, but lack the capabilities and talent for that. And last but not least are those groups you have not heard from in the news. They do have proper infosec.
I've heard of criminals using MMORPG DM's to communicate back in the day, not sure what happened to those guys.
Another way to stay under the radar. IIRC there was a case where information was passed on an image board by means of using random-looking filenames that actually encoded messages.