iPhone Dev Team

Now that redsn0w has been updated to jailbreak iOS 4.2.1 you may be wondering what's involved in actually jailbreaking your iPhone. Here are some tips and instructions to help. First of all, if you have an unlocked iPhone don't update your device to the official iOS 4.2.1 or use the redsn0w 0.9.6b4 jailbreak. You will lose your unlock.

UPDATE: Comex has released an easier method for newer 4.x firmwares. Click here for instructions on how to use JailbreakMe 3.0 to jailbreak your device.

Always back up your SHSH files before jailbreaking. This will preserve your ability to downgrade in the future. You must also find out if a tethered jailbreak is necessary on your device.

Just one day after Apple's release of the iOS 4.2 firmware update, iPhone Dev-Team has made public the first updated jailbreaking tool for Mac OS X and Windows. Redsn0w version 0.9.6b4 can be used immediately for those who are not concerned about using the ultrasn0w unlock. iPhone 3G and older iPhone 3GS users will be happy to know that the jailbreak is untethered.

For newer iPhone 3GS and iPhone 4 users, this version currently requires a computer to boot into the jailbroken state. The iPhone Dev-Team is working with @comex on a fix that would untether the iPhone 4 jailbreak once and for all. Unlockers can expect a new version of ultrasn0w for the iPhone 3G and iPhone 3GS as early as next week.

The jailbreak community has been active lately. Thanks to a surprise release of the limera1n jailbreak tool from Geohot, the release of Greenpois0n was delayed. Now both hacks use the same unpatchable bootrom exploit and are available to the iOS device-owning public.

In the meantime, the SHAtter exploit initially planned for Greenpois0n has been shelved for future use. Apple will surely fix the bootrom exploit in the next round of iOS hardware, however this time the jailbreak developers have a countermeasure ready for action.

We know that MuscleNerd was showing off his brand new jailbroken iPod touch 4G the other day. Looks like the same iOS vulnerability has just been used to jailbreak a second-generation Apple TV. After successfully using the SHAtter exploit MuscleNerd posted video of the Apple TV being accessed with ssh.

SHAtter tricks the Apple TV into restoring with a pre-jailbroken IPSW from PwnageTool. The same exploit should work across all iOS devices including the iPhone 4. Chronic Dev Team members are developing jailbreak tools for public release based on the SHAtter bootrom vulnerability. This method will be much more difficult for Apple to contend with, as a firmware update can't prevent the issue.

iPhone Dev-Team member MuscleNerd has posted a screenshot of his jailbroken iPod touch 4G. A bootrom vulnerability has been discovered by @p0sixninja that will make it possible to jailbreak all iOS devices running the latest firmware including the iPhone 4. Chronic Dev Team members are currently developing new jailbreak tools based on the vulnerability, otherwise known as SHAtter.