Sony have just released firmware update 6.20 for the PS4, which was a bit surprising given that 6.10 was the next update to be expected after going through extensive beta in November.
As always for these minor updates, the changelog is intentionally vague and simply states that “This system software update improves system performance”. In other words, this could be anything from a minor patch for some specific game, to some critical vulnerability fix.
Should I update my PS4 to 6.20?

You know the drill: if you expect your PS4 to be hacked, we usually don’t recommend you update your console.
In particular, this update comes as 3 different “exploits” have been recently announced for the PS4 (although none of them confirmed to be a massive game changer at this point). Zecoxao’s upcoming “super secret method” in particular, seems to specifically target firmware 6.02, and there is no word at this point whether it works on the latest firmware 6.20 or not.

via http://wololo.net/2018/12/12/ps4-firmware-update-6-20/