# PS4 4.55 Kernel Exploit
In this project you will find a full implementation of the "bpf" kernel exploit for the PlayStation 4 on 4.55. It will allow you to run arbitrary code as kernel, to allow jailbreaking and kernel-level modifications to the system. This release however, *does not* contain any code related to defeating anti-piracy mechanisms or running homebrew. This exploit does include a loader that listens for payloads on port `9020` and will execute them upon receival.
This bug was discovered by qwertyoruiopz, and can be found hosted on his website [here](http://crack.bargains/455/).
## Patches Included
The following patches are made by default in the kernel ROP chain:
1) Disable kernel write protection
2) Allow RWX (read-write-execute) memory mapping
3) Syscall instruction allowed anywhere
4) 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.
- Payloads from 4.05 should be fairly trivial to port unless they use hardcoded kernel offsets
- I've built in a patch so the kernel exploit will only run once on the system, you can make additional patches via payloads.
- A custom syscall is added (#11) to execute any RWX memory in kernel mode, this can be used to execute payloads that want to do fun things like jailbreaking and patching the kernel.
Massive credits to the following: