In today's video, we talk about the latest update to FutureRestore, a tool that helps to #downgrade and #upgrade to #unsigned iOS versions with saved SHSH2 blobs. The tool has just been updated to support iOS 12 and A12 devices, however, do keep in mind that FaceID devices are not supported yet. The updated has been released on GitHub as open source by developer s0uthwest for macOS.
#FutureRestore has been historically used since iOS 10 days to perform restores to older firmware or from older ones to newer firmware using saved SHSH2 blobs. This is rather useful when you run a very old iOS version because it's jailbroken but things start to fall apart (e.g. apps no longer support that version, etc). At that point, with a bit of luck, if you have saved SHSH2 blobs for a newer version that is jailbroken, you can easily use FutureRestore to jump to it even if that version has long been unsigned. Imagine jumping from #iOS 10 which is a bit outdated at this point to 11.3.1 which has the latest jailbreak at the time of speaking. This is possible if you have iOS 11.3.1 blobs saved and iOS 12.x SEP and Baseband are compatible.
The SEP and Baseband compatibility is, unfortunately, a necessary thing. When using FutureRestore you combine various IPSW files into one. You take the root file system, ramdisks, kernel and boot files from the version you want to downgrade to, but you add the SEP (Secure Enclave Processor) and the Baseband of the latest signed version or a version prior to the latest that is still signed. If you are lucky and the difference isn't too big as to break things, the restore would proceed and everything works fine. Not an easy task but it gives jailbreakers a second chance. Of course, to be able to downgrade from iOS 12.x to iOS 11.3.1 for example, aside from the SEP and baseband compatibility, there also has to exist either a jailbreak for iOS 12 or a nonce setter tool, otherwise, the blobs cannot be used. It's not required when going from a jailbroken version to a non-jailbroken one, however.