iPhone 4S and iPad 2 Downgrade From iOS 5.1 To iOS 5.0.1, Everything You Need To Know
Just couple of days ago we reported that famous iOS hacker/developer and brain behind Sn0wbreeze found a loop hole in iPhone 4S and iPad 2 which allowed him to downgrade his iPad 2 and iPhone 4S from iOS 5.1 to iOS 5.0.1. At that time it was just iPad 2 which was downgraded from 5.1 to iOS 5.0.1 but now he has successfully downgraded his iPhone 4S as well. Before I dive in to details I will give you a little summary of this issue. As we don’t have an A5 bootrom exploit it was impossible to downgrade iOS firmware even with saved SHSH blobs. Currently you can only restore an iOS firmware on A5 devices which is being signed by Apple (right now it’s iOS 5.1).
iH8sn0w has been working with Semaphore aka notcom creator of TinyUmbrella (a tool which allows you to save your iOS device’s SHSH blobs). iH8Sn0w and Notcom worked in collaboration and used this ‘loophole’ to downgrade both iPad 2 and iPhone 4S. Now coming to the main point and “one and only question”; how did they do it. Well no information has been made public about this ‘loophole’ but before you freak out that why they’re not making it public believe me it’s for the greater good. This is something which they should hold on to for a long time because things are going to get dirty in next couple of iOS updates and upcoming iPhone 5. Another thing which confused a lot people is the need of SHSH blobs, YES you will need SHSH blobs of a that specific firmware you’re downgrading to. If you don’t have your SHSH blobs saved for your iPhone 4S or iPad 2 then you won’t be able to downgrade.
Right after the first announcement a lot of people confused it with baseband downgrade. This is not related to baseband downgrade in any way, there’s no way to downgrade your baseband. Both these developers have no plans to release it publicly any time soon because of the reason I tried to explain above. There are two possibilities 1) they may release it after iOS 5.1′s untethered jailbreak is public 2) after iPhone 5′s launch.
Details about this loophole are scant so it would be too early to speculate or conclude anything. But we will keep you updated on this.