With the recent release of the 4.05 Kernel exploit by SpecterDev, I’m sure everyone’s busy trying to figure out how to run it and what it can do. The first step, if your PS4 is not running firmware 4.05, is to update to 4.05. But you need to be careful not to update to the latest firmware (5.03 at the time of this writing), so follow this guide.

Important: This guide is for you if your PS4 is running on a firmware lower than 4.05. If your console is on firmware 4.06 or higher, this guide is not for you. Additionally, there is no publicly known way to downgrade a PS4 from a higher firmware to 4.05. Any site claiming that it is possible is either misguided or trying to trick you. If your PS4 is running a firmware higher than 4.05, you might want to try and get your hands on a 4.05 PS4.

1. Download Firmware 4.05

The first step is to get a copy of firmware 4.05. At the time of this writing, softpedia have it up for download here. It can also be found on sce.party.

No mater where you get your copy of the firmware, you want to be extremely careful here and not download an incorrect version. The last thing you want to do is end up on firmware 5.03 because you downloaded the wrong file! The MD5 checksum of PS4 firmware 4.05 is 203c76c97f7be5b881dd0c77c8edf385. Windows users can use free tool WinMD5 to check the MD5 of the file they download. If it doesn’t match, don’t try to install.

2. Prepare your PS4: disable automatic updates

First of all, you’ll want to make sure your PS4 isn’t connected to the internet while you’re doing any of this.

There are a few things you will want to do with your PS4 before you start playing with the hack. You might as well do some of thes now. In particular

• Disable automatic updates: In Settings –> System –>Automatic Downloads and Uploads, make sure “System Software Update Files” and “Install Automatically” are both unchecked

You might also want to disable internet connection in rest mode:

3. Copy the PS4 4.05 Firmware update to a USB Key

You’ll need a USB key with about 400MB free. Sony don’t recommend a particular format, but mine was formatted in FAT32, because that’s what they used to enforce on PS3.

On the USB Key, create a folder named PS4, and under that folder, another folder named UPDATE. Inside that folder, copy your PS4 Update file. It needs to be named PS4UPDATE.PUP.

Your USB folders should look like this

4. Install

Turn the PS4 on if it’s not already, and insert the USB Key.

Go to Settings –> System Software Update, The PS4 should tell you that it found firmware update 4.05. If not, go back to the previous steps, and make sure you have everything in place (a typical mistake is to have the update file with the wrong name, or in the wrong folders).

When the PS4 tells you update 4.05 is available, click “Next” and follow the instructions on the screen.

You’re done!

Stay tuned for more details on the PS4 4.05 Kernel Exploit!