Installing firmware 9.00 on your PS4 is a common step for those looking to stay on a stable, exploitable version for homebrew. Since Sony only offers the latest version (currently 12.02 or higher), you must download the 9.00 file from third-party archives and install it manually via USB. 1. Preparation
Before You Begin
Check Your Current Firmware: Go to Settings > System > System Information. Your current version is listed next to "System Software."
USB Drive Requirements: A USB drive formatted as exFAT or FAT32. The drive must have at least 1.5 GB of free space.
Folder Structure: On the USB drive, create a folder named PS4. Inside that, create another folder named UPDATE.
Stable Power: Ensure your PS4 is connected to a reliable power source (not running on low battery for a PS4 Slim/Pro with a power cable). An interruption during installation can brick your console.
What’s New / Changed in Firmware 9.00?
Party Safety Features: Enhanced parental controls for voice chats in parties. Only friends can be added to parties by default (adjustable).
PS Remote Play Improvements: General stability and performance for Remote Play on PC/mobile.
System Performance: “This update improves system performance.” – Standard Sony patch note.
For Developers/Homebrew: Version 9.00 includes an exploit (WebKit vulnerability) that later allowed custom firmware (CFW) and homebrew enablers like GoldHEN. This is why 9.00 became a sought-after version in the modding scene.