PS4 6.20 WebKit Code Execution Exploit PoC by SpecterDev!

Proceeding the release of PS4 Firmware 6.50, his previous PS4 Exploit Documentation, GH Clone Demo, the 6.20 Dev Build Strings and 6.50 Dev Build Strings as promised today @SpecterDev released via Twitter a PS4 6.20 WebKit Code Execution Exploit PoC (Proof-of-Concept) using CVE-2018-4441 to obtain RCE crediting lokihardt for the vulnerability used.

From the Tweets below, he states that unlike the PS4 6.XX JSC_ConcatMemcpy WebKit Exploit which wasn't a complete exploit, this one grants code execution in userland for PS4 scene developers!

Download: PS4-6.20-WebKit-Code-Execution-Exploit-master.zip / GIT / Live Demo / 6.20-FS.zip (323 MB - FULL 6.20 Fs with modules, decrypted) / Kernel_Dump_620-1.zip (20.5 MB - 6.20 kernel) / 6.20 kernel offsets via LightningMods

For newbs: This is a 6.20 PS4 WebKit (Userland) exploit and not a Kernel-level exploit, meaning until a fully implemented 6.20 Kernel exploit is publicly available you won't be able to jailbreak these PlayStation 4 consoles so don't update!

Also for those that updated already, if you can't get a second jailbroken console to run PS4 game backups then while you're waiting for a PlayStation 4 jailbreak (no ETA) it's recommended to get a Verified Badge via Discord to access the private areas.

To quote from the README.md: PS4 6.20 WebKit Code Execution PoC

This repo contains a proof-of-concept (PoC) RCE exploit targeting the PlayStation 4 on firmware 6.20 leveraging CVE-2018-4441. The exploit first establishes an arbitrary read/write primitive as well as an arbitrary object address leak in wkexploit.js.

It will then setup a framework to run ROP chains in index.html and by default will provide two hyperlinks to run test ROP chains - one for running the sys_getpid() syscall, and the other for running the sys_getuid() syscall to get the PID and user ID of the process respectively.

Each file contains a comment at the top giving a brief explanation of what the file contains and how the exploit works. Credit for the bug discovery is to lokihardt from Google Project Zero (p0). The bug report can be found here.

Note: It's been patched in the 6.50 firmware update.

Files

Files in order by name alphabetically;

• index.html - Contains post-exploit code, going from arb. R/W -> code execution.
• rop.js - Contains a framework for ROP chains.
• syscalls.js - Contains an (incomplete) list of system calls to use for post-exploit stuff.
• wkexploit.js - Contains the heart of the WebKit exploit.

Notes

• This vulnerability was patched in 6.50 firmware!
• This only gives you code execution in userland. This is not a jailbreak nor a kernel exploit, it is only the first half.
• This exploit targets firmware 6.20. It should work on lower firmwares however the gadgets will need to be ported, and the p.launchchain() method for code execution may need to be swapped out.
• In my tests the exploit as-is is pretty stable, but it can become less stable if you add a lot of objects and such into the exploit. This is part of the reason why syscalls.js contains only a small number of system calls.

Usage

Setup a web-server hosting these files on localhost using xampp or any other program of your choosing. Additionally, you could host it on a server. You can access it on the PS4 by either;

1. Fake DNS spoofing to redirect the manual page to the exploit page, or
2. Using the web browser to navigate to the exploit page (not always possible).

Vulnerability Credit

I wrote the exploit however I did not find the vulnerability, as mentioned above the bug (CVE-2018-4441) was found by lokihardt from Google Project Zero (p0) and was disclosed via the Chromium public bug tracker.

Resources

• Chromium Bug Report - The vulnerability.
• Phrack: Attacking JavaScript Engines by saelo - A life saver. Exploiting this would have been about 1500x more difficult without this divine paper.

Thanks

• lokihardt - The vulnerability
• st4rk - Help with the exploit
• qwertyoruiop - WebKit School
• saelo - Phrack paper

PS4 6.20 WebKit Proof of Concept (PoC) via Stefanuk12

 

[btaggs]

@Tar What do you think it should be doing on your 5.56 ps4? because it literally does nothing. It opens up a security hole. You can't see it or do anything with it so I am not sure what you are expecting it to do.

 

[Vicodin10]

This is awesome! yaaaaa

 

[zia]

upcoming Jailbreak for 6.20

 

[482877494]

So Specter again hm?
Love this guy

 

[kizabg]

 

[SirSilvan83]

Means, existing kexploit definitively works with 6.50?
Good news for Devs bad news for kids who are waiting for public kexploit

 

[drenovackg]

This is awesome. Jailbreak is coming

 

[SSShowmik]

@Chaos Kid that is why scene devs are waiting long to release a jailbreak. This way, those who buy games will have already bought those games by then. Most sales and profit of games happen in the first year of release. So game devs aren't losing much in terms of finance/sales.

Trying out backups before buying them is a great motive. For example, anthem and jump force, two games people would not have bought if they knew before hand how game breaking their flaws are. Everything has a good and a bad.

 

[lucasnooker]

I am getting confused. People are saying the kexploit works on newer firmwares so won't be released until Sony patches it but isn't this Web exploit a new completely separate vulnerability that was since patched in 6.50?

In other words meaning if this specific vulnerability is kexploited wouldn't it be a completely separate and new method from the currently existing one that works in private? So we could get a public 6.20 jb and the one that still works in private will live on for future firmwares?

 

[Thien Tran]

Just release 5.55 or 6.20 jb if it existed and if Sony patch it. Let worry about it later.