iPhone Dev-Team Releases Untethered Jailbreak for iOS 4.3.1
The iPhone Dev-Team has released an untethered jailbreak for iOS 4.3.1. The jailbreak implements the untether developed by i0n1c.
The 4.3.1 untether exploit comes courtesy of Stefan Esser (@i0n1c on twitter), a security researcher based in Germany. Stefan has a long history of vulnerability research, and ironically his first contribution to the iPhone jailbreak community was improved security — last year he beat Apple to the punch and implemented ASLR for jailbroken iPhones with his "antid0te" framework. We're happy to see that Stefan then turned his iPhone attention over to an untethered jailbreak exploit!
Supported devices are the iPhone 4, iPhone 3GS, iPod touch 4G, iPod touch 3G, iPad 1 and Apple TV 2. The iPad 2 is not supported as of yet.
You can download either RedSn0w or PwnageTool to perform the jailbreak. Download links can be found here:
● RedSn0w (Windows, Mac)
● PwnageTool (Mac)
We will be posting more tutorials on how to perform the jailbreak momentarily.
Tutorials:
● iPhone 4 (Windows, Mac)
● iPhone 3GS (Mac)
IMPORTANT: Ultrasn0w users don't update yet! The iPhone Dev-Team still needs to release an update to ultrasn0w for the 4.3.1 firmware.
We need to first release an update to ultrasn0w that fixes some incompatibilities when FW 4.3.1 is used on the older basebands supported by ultrasn0w. And remember once we do fix ultrasn0w for 4.3.1 (we'll announce it here and on twitter), you must only get there via a custom IPSW from PwnageTool, Sn0wbreeze or xpwn! Don't ever try to restore or update to a stock IPSW, or you'll lose the unlock!


Before we start into the tutorial to unlock iPhone 4 I want to start by explain what unlocking actually is. Unlocking is the removal of SIM restrictions on your iPhone so that you can use any carrier you want. This is what most people want to be able to do as it can save them a great deal of money on their monthly bills. It also means that you can continue to use the service provider that you are currently using. With that out of the way, let’s move on to this step by step Unlock iPhone 4 tutorial.
Step 4: You should now have the new URL registered so all you have to do is hit the done button. You will now be able to find the ultrasn0w application and this will automatically unlock iPhone 4. The next step in this process is to turn off your device.