The group also identified weaknesses in the PlayStation 4's GPU and the PlayStation 4's southbridge chip.
The PS4 used for the hack was running on PS4 firmware 1.76. Sony recently issued firmware 3.11 to consoles. While the bug has now been patched, it's believed the jailbreak could be altered to achieve the same outcome on more recent firmwares.
The hack does not mean that you'll be able to install pirated games in your console. Sony has been trying to ensure that unsigned code could not be run on the console. The company requires that the machine runs on the very latest software, meaning hacker groups still have a long way to go before the PlayStation 4 is made truly open to hobbyists.
In the two years since the PlayStation 4 first went on sale, hackers have achieved limited success in their efforts to open up the console. In June, a Brazilian team claimed the first PS4 "jailbreak," which involved the cumbersome process of copying the entire hard drive of a hacked machine using a Raspberry Pi, but it took until this month for a tinkerer to fully circumvent Sony's content protections.