Those of you following the PS4 hacking scene right now will have heard of CTurt, he has been documenting his findings whilst hacking the PS4 via his Github.
The PS4 native is called Orbis OS, which is a modified version of FreeBSD 9.0 which was released on January 12, 2012.
CTurt's kernel code execution was based on the PS4 firmware version 1.76 using BadIRET exploit which has been patched on later firmware versions. CTurt released an open source PS4-SDK which would allow others to research the PS4.
Although CTurt did officially Jailbreak the PS4, he stated that he wanted no part in releasing a functional Jailbreak for the masses, custom firmware (CFW) or anything that would encourage piracy on the PS4.
"I've recently been getting a lot of unwanted attention from people pleading me to release a "CFW" or "Jailbreak" so that they can pirate video games on their PS4.
I want to make very clear that I've primarily been doing this research as a learning exercise because I have a passion for InfoSec. This is partly the reason why I've tried to take a such an open approach; and I'm very grateful to hear whenever another aspiring security analyst tells me that they have found these articles helpful."
It should be no suprise that CTurt began to help FreeBSD security team HardenedBSD, patch kernel exploits that he had found whilst researching the PS4.
"Yay. Got kernel panic from one of the bugs I found yesterday" says CTurt in a Tweet which contained a link to a FreeBSD bug report where he disclosed this kernel exploit along with yet another one here.
HardenedBSD was formed in 2014 by Oliver Pinter and Shawn Webb, as a security-enhanced fork of FreeBSD. The HardenedBSD Project works on exploit mitigation and security for FreeBSD.
Shawn Webb welcomed CTurt to the team by posting an announcement on their website which said, "We've added a new member to the HardenedBSD team! CTurt will be working with us to research, exploit, and produce patches for kernel-level vulnerabilities. We'll be working on getting these kernel security enhancements upstreamed to FreeBSD after the fixes have been deemed stable in HardenedBSD first."