After years of work, hackers have finally managed to unlock the PS4 hardware with an exploit that lets the system run homebrew and pirated PS4 software. In a somewhat more surprising discovery, those hackers have also unlocked the ability to run many PS2 games directly on the console, using the same system-level emulation that powers legitimate PlayStation Classics downloads.

While hackers managed to install Linux on the PS4 years ago, the biggest breakthrough in the PS4 hacking scene came late last month, when two different teams of hackers released a WebKit exploit for version 4.05 of the PS4 firmware.

That firmware was patched (and automatically updated on many systems) in late 2016, and there's currently no known way to downgrade an updated system to the older firmware, which limits the range of consoles that can run the exploit. For compatible consoles, though, the kernel-level exploit allows for pretty much full control of the system, including the running of unsigned code.

Exploit in hand, the hacking community has quickly gotten to work on a "package creator"—which recompiles homebrew and decrypted PS4 software into a form that will be accepted by an unlocked PS4—and a "homebrew enabler"—which adds a PS4 settings menu option to download and install such code packages directly to a PS4. Copies of games released since early 2017, which require more recent firmware, can't be run using this method, but all older PS4 titles appear to run without much issue after running through this hacking gauntlet.

The same basic methodology also seems to work with copies of PS2 games, though these need a little bit of extra massage and recompilation with special tools to fool the PS4 into making them work with its built-in PlayStation Classics emulator . Tests so far show this basic method working on games ranging from Dragon Ball Z Budokai Tenkaichi 3 to Klonoa 2 , the latter of which didn't even work on the PS3

While we're still a long way off from just putting a PS2 disc into a PS4 and getting it to run, this hack shows that such backward compatibility would likely work on standard PS4 hardware if Sony decided to support it. And now that the floodgates have been opened, the hacking community will likely shift to trying to find additional exploits for more recent PS4 firmware—or a more-generalized method that can downgrade a system to an exploitable earlier firmware version. If that happens, Sony's previously tight control over PS4 software distribution could be in serious jeopardy.