Aaaand we’re back, after an extended delay, to … continue talking about hacking PS4 peripherals 😅.

This time, the DUT is the PS4 Virtual Reality peripheral: PSVR. We managed to find some major flaws - breaking secure boot and extracting all key material; let’s go!

This post describes another way to attain code execution on Aeolia (actually, the southbridge revision on PS4 Pro which was used in this case is named “Belize”).
This exploit differs from the previously documented method as it does not have the prerequisite of gaining control of the APU. Additionally it is fairly generic and therefor workable on all currently released hardware and software versions of PS4.

In the PS4 Aux Hax series of posts, we’ll talk about hacking parts of the PS4 besides the main x86 cores of the APU.
In this entry, we’ll step outside of the PS4 itself, and take a look at pwning the main handheld controller used by the system.

In the PS4 Aux Hax series of posts, we’ll talk about hacking parts of the PS4 besides the main x86 cores of the APU.
In this entry, we’ll recount some parts of the path taken to get permanent arbitrary code exec on syscon.

In the PS4 Aux Hax series of posts, we’ll talk about hacking parts of the PS4 besides the main x86 cores of the APU.
In this first entry, we’ll give some background for context and describe how we managed to run arbitrary code persistently on Aeolia, the PS4 southbridge.

What if a secure device had an attacker-viewable crashdump format?
What if that same device allowed putting arbitrary memory into the crashdump?
Amazingly, the ps4 tempted fate by supporting both of these features!
Let’s see how that turned out…

Plenty of time has passed since we first demonstrated Linux running on the PS4.

Now we will step back a bit and explain how we managed to jump from the browser process into the kernel such that ps4-kexec et al. are usable.

CVE-2012-0217 was reported by Rafal Wojtczuk but ironically, it was fixed for Linux in 2006 as shown by CVE-2006-0744 without receiving much attention.

It is quite an interesting vulnerability on many aspects. Among them, and thanks to its hardware basis, it impacts many operating systems. For instance, as long as they run on a Intel processor in long mode (obviously), FreeBSD, NetBSD, Solaris, Xen and Microsoft Windows have been reported to be vulnerable. This therefore gives us quite an incentive to develop an exploit ;).

If you haven’t yet read Xen’s blog post The Intel SYSRET privilege escalation please do because we won’t go again into too much details about the vulnerability itself.

Without further delay, let’s dig right into the FreeBSD exploitation!