chendochap / poobs4

PS4 9.00 Kernel Exploit

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Summary

In this project you will find an implementation that tries to make use of a filesystem bug for the Playstation 4 on firmware 9.00. The bug was found while diffing the 9.00 and 9.03 kernels. It will require a drive with a modified exfat filesystem. Successfully triggering it will allow you to run arbitrary code as kernel, to allow jailbreaking and kernel-level modifications to the system. will launch the usual payload launcher (on port 9020).

Patches Included

The following patches are applied to the kernel:

1. Allow RWX (read-write-execute) memory mapping (mmap / mprotect)
2. Syscall instruction allowed anywhere
3. Dynamic Resolving (sys_dynlib_dlsym) allowed from any process
4. Custom system call #11 (kexec()) to execute arbitrary code in kernel mode
5. Allow unprivileged users to call setuid(0) successfully. Works as a status check, doubles as a privilege escalation.
6. (sys_dynlib_load_prx) patch
7. Disables sysVeri

Short how-to

This exploit is unlike previous ones where they were based purely in software. Triggering the vulnerability requires plugging in a specially formatted USB device at just the right time. In the repository you'll find a .img file. You can write this .img to a USB using something like Win32DiskImager.

Note: This will wipe the USB drive, ensure you select the correct drive and that you're OK with that before doing this

When running the exploit on the PS4, wait until it reaches an alert with "Insert USB now. do not close the dialog until notification pops, remove usb after closing it.". As the dialog states, insert the USB, and wait until the "disk format not supported" notification appears, then close out of the alert with "OK".

It may take a minute for the exploit to run, and the spinning animation on the page might freeze - this is fine, let it continue until an error shows or it succeeds and displays "Awaiting payload".

Extra Notes

• Unplug the USB before a (re)boot cycle or you'll risk corrupting the kernel heap at boot.
• The browser might tempt you into closing the page prematurely, don't.
• The loading circle might freeze while the webkit exploit is triggering, this doesn't yet mean that the exploit failed.
• The bug predates firmware 1.00, so 1.00-9.00 should be exploitable using the same strategy (you will need a different userland exploit & gadgets).
• You can replace the loader with a specific payload to load stuff directly instead of doing it through sockets.
• This bug works on certain PS5 firmwares, however there's no known strategy for exploiting it at the moment. Using this bug against the PS5 blind wouldn't be advised.
• Please don't open issues to tell me that there are none... nor make attempts at making me do your homework for you.
• This repository does not provide anything beyond the initial kernel patches that allow you to execute payloads. If you encounter issues with certain payloads you should report your issues to the developers of those payloads through whatever means they make available to you.
• The name of the repository is a fusion of the words 'ps4' and 'OOB', the latter being the kind of vulnerability this implementation attempts to exploit, any other interpretation is purely coincidental & unintended.
• As stated before, this bug was found by diffing the 9.00 and 9.03 kernels, this does imply that the bug was fixed on 9.03.

Contributors

• laureeeeeee
• Specter
• Znullptr

Special Thanks

• Andy Nguyen
• sleirsgoevy - 9.00 Webkit exploit