PS4 5.05 BPF Double Free Kernel Exploit Writeup
Welcome to the 5.0x kernel exploit write-up. A few months ago, a kernel vulnerability was discovered by qwertyoruiopz and an exploit was released for BPF which involved crafting an out-of-bounds (OOB) write via use-after-free (UAF) due to the lack of proper locking. It was a fun bug, and a very trivial exploit. Sony then removed the write functionality from BPF, so that exploit was patched. However, the core issue still remained (being the lack of locking). A very similar race condition still exists in BPF past 4.55, which we will go into detail below on.