PS5: Firmwares 6.00 to 7.61 are getting kernel read/write. PS5-jar-loader released with kernel r/w support for 6.00 to 7.61

PS5 Developer Hammer-83 released PS5-JAR-Loader 4.01 a few days ago. The utility lets you run payloads via the bd-jb exploit, on PS5 Firmwares up to 7.61 included. This new release leverages a discovery by hacker flat_z, which allows kernel read/write even on the higher firmwares 6.00 to 7.61.

To the end user, this means you’ll start to see more useful payloads and utilities for your hacked console, in particular if you’ve been sitting on Firmwares 6.00 to 7.61. PS5 JAR Loader itself comes with Debug Settings and an FTP Server, to get you started.

What is PS5 JAR Loader

From the Readme:

This project uses vulnerabilities discovered in BD-J layer of PS5 firmware version 7.61 and earlier to deploy a loader that is able to listen to JAR files and execute their main class. This makes it easy to burn the BD-R disc with the loader just once and then keep on running new versions of the experimental code. This repository provides all the necessary setup needed to create both the loader BD-R disc filesystem and the JAR to send to the PS5.

In other words, PS5 JAR Loader is a payload loader for the bd-jb exploit. Instead of having to burn a Blu Ray disc for every single payload you want to load, you just need to burn a disc with PS5 JAR Loader, which in return will load any payload you send to it via telnet. It might sound complicated, but there are tons of tutorials around on how to run it, and once you’re used to it it’s fairly straightforward.

Kernel Read/Write on PS5 Firmware 6.00+, via the GPU

A few weeks ago, hacker flat_z disclosed a technique to get kernel read/write on “higher” Firmwares 6.00+, by leveraging GPU DMA routines. The hacker shared his code here back in January. This allowed Hammer83 to implement the technique into PS5 JAR Loader, to enable features that require Kernel access on the console.

While PS5 Firmwares up to 4.51 included have enjoyed a solid Jailbreak environment with lots of features, Firmwares 5.00 to 7.61 have been “stuck” in a situation where, although a Jailbreak is available to them (the umtx exploit), features are restricted. While Firmware 5.00 to 5.50 have good hopes to seeing Sleirsgoevy‘s “kstuff” (a powerful self-contained PS5 debugger that emulates kernel read/write) being added eventually (which would unlock all the features we enjoy on the 4.51 Jailbreak), it has been known for some time that Kernel read/write would be more complicated from 6.00 onward, as Sony have patched some of the vulnerabilities involved with kstuff.

Long story short, this new technique for kernel read/write is probably a game changer for the scene. For now we’re seeing it in action on Firmware 6.00 to 7.61 with Hammer83’s payload loader, but this could open more doors quite soon.

Importantly, we’re talking of PS5 consoles with an integrated Blu-Ray reader here. The Digital Edition versions are out of the picture for this particular release (technically, exploits exist that use a LUA vulnerability for Digital consoles, and flat_z has an implementation of the GPU Kernel read/write for those as well. It’s being added to the SDKs, for the lucky few who do have access to the exploitable games)

Download PS5 JAR Loader 4.01

You can Download PS5 JAR Loader on the project’s github here. Check the readme for setup and how to run.