There’s been a lot of misinformation, or misunderstandings, about the status of hacking for firmwares 5.xx, or, technically, for any firmware above 4.55 (so yes, this includes 4.70).
Hacker Qwertyoruiop has somewhat clarified the situation, but some people seem to either read too much between the lines, or not enough in some cases. So here goes my attempt at clarifying:
OK, remember this part and get it through your hard skull
In order to fully hack a PS4, you generally need a combination of two exploits: 1) an entry point from one of the user processes, a.k.a a usermode exploit. This is typically a webkit exploit (but could also be an exploit in any other user app of the console, such as a game). And 2), a privilege escalation exploit (often referred to as “kernel exploit”), in order to get “root” access, in other words full access to the console.
The usermode exploit gives you enough access to run a bit of code: enough to run the kernel exploit which will unlock “real” access to the console.
Without both of these, you can’t really do much: A kernel exploit alone doesn’t give you anything, because you don’t have a way to actually activate it from anywhere. Conversely, a usermode exploit alone gives you some level of control on the console, but typically not enough to do anything “fun” (note that on that part, things could evolve with time: on some consoles, usermode exploits have led to great homebrew loaders such as *cough* VHBL *cough*)
If you’re above 4.55: Hacker Qwertyoruiop has stated that Sony patched his kernel exploit on firmware 5.50. This automatically implies that he is in possession of a kernel exploit that apparently works up to firmware 5.05 included, but not on 5.50. Clear enough?
In the exact same tweet, he explained that he has improved the recently disclosed Webkit exploit (remember: usermode exploit) and tested it on firmware 5.50. This confirms that webkit exploit is valid up to firmware 5.50 included. And you can actually play with it on your PS4 from the url provided by the hacker (http://crack.bargains/550/). Remember what I wrote above, though: a usermode exploit is fun, but does not give you much to play with without a kernel exploit.
Qwertyoruiop has also said he updated to firmware 5.50, and confirmed it by showcasing the Webkit exploit. He strongly implied that he is now looking for kernel exploits on the latest firmware.
Please note that to my knowledge, Qwertyoruiop has not stated anywhere that he would release his kernel exploit (the one that got patched in 5.50). So, although there is hope that such a thing could eventually be released (the hacker has a pretty good track record of releasing stuff on the PS4), there is no guarantee of that at the moment.
So let’s summarize.
Can I hack my PS4?
if (x <= 4.55) – If you’re on firmware 4.55 or below: Yes, your PS4 is fully Jailbreakable, check here for details.
if (4.55 < x < 5.50) – If you’re on a firmware above 4.55, but strictly below 5.50: There’s a public Webkit exploit you can play with (remember, it won’t bring you anything, as an end user). Additionally, we *know* there exists at least one kernel exploit for your console (Qwertyoruiop’s one, mentioned above), but no hacker has promised any release at the moment. Therefore you’ll often see it mentioned as a “private kernel exploit”.
if (x == 5.50) – If you’re on firmware 5.50: There’s a public Webkit exploit you can play with (Remember, it won’t bring you anything, as an end user). However, there is no public knowledge of a kernel exploit working for your console at the moment, let alone a promise of a release for it.
In conclusion, always stay on a firmware as low as you possibly can. In particular at the moment, if you’re on 5.0x or 4.70, do not update to 5.50: there’s more chance of a Jailbreak for you than for people on 5.50. If you want the best of both worlds, you need 2 PS4s. Buy a secondary one that you’ll keep on a shelf until a hack gets released. It could be weeks, it could be months, nobody really knows for sure.