Like the Nintendo Switch scene the PS4 Hacking Scene has been mad lately and heres some more great news:
Volodymyr Pikhur has released a presentation of a 'rest mode' hack for PS4. Quote: 'This presentation will talk about how custom Southbridge silicon, responsibe for background downloads while main SoC is off, didn’t help to secure Playstation 4. It will explain how a chain of exploits combined with hardware attacks will allow code to run in the context of the secure bootloader, extract private keys, and sign a custom kernel.' Thanks goes to Wololo for the heads up, his story is here. This seems to work on firmware 5.xx but can't confirm at the moment.