The “method” that allows piracy on PS4 firmware 6.20 leverages a glitch in the PS4 “Primary console” setup mechanism.
Sony lets you use multiple consoles with the same PSN account, in theory to let you access your games from wherever you are in the world. However, only your “primary” console can play your PSN games without being connected to the internet.
The glitch revealed today basically lets you activate a PS4 as your primary console, then deactivate it while keeping the benefits of playing downloaded games while offline. Repeat the steps multiple times with a single PSN account loaded with games, and you have the possibility for mass scale piracy.
There are of course significant drawbacks to the technique: first of all, it is very likely that Sony will patch it in the days, if not the hours (given that it requires online activation of the console) to come. Secondly, you’ll need to find a very good friend, with a PSN account loaded with games, who is willing to share their account credentials with you at least once, in order for you to get that person’s games. Last but not least, it is very likely that Sony will take action on accounts that have suspicious activity, including activating/deactivating a large number of PS4s in a short amount of time.
So far, the scene’s reaction to the announce has been pretty lukewarm. Given the risks, it’s probably not worth it for your typical PS4 owner. It’s also very likely that some black market shops all over the worlds had been using this technique or a similar one to sell PS4s loaded with pirated games, something that reminds us of the “Brazilian jailbreak” of a few years ago. So multiple people have said they are basically not impressed.
Long story short, we definitely do not recommend that you even attempt this technique: you run a huge risk of getting your PSN account, and associated hardware permanently banned from the PSN if you try. Nevertheless, those willing to take the risk can follow the steps described below, as taken directly from the video.

http://wololo.net/2018/12/30/ps4-6-2...-disappointed/