Apple seems to have accidentally started signing older and jailbreakable iOS versions earlier today, which allowed people to downgrade their devices.
It seems the signing window was open for just 1 hour. A few iOS versions from iOS 6 to iOS 11.2 were being signed briefly. iOS 11.1.2 wasn’t being signed, otherwise, it would have been a great opportunity for jailbreakers to downgrade to the latest iOS version that can be jailbroken using LiberiOS jailbreak.
Based on this reddit thread, quite a few users were able to downgrade to an older iOS version that can be jailbroken. Some users who had the presence of mind also managed to save SHSH2 blobs, which would have meant that it would have saved the SHSH for several jailbreakable iOS versions that were being signed because of the bug.
In some cases, users were happy that they were able to downgrade their iPhone 7 to iOS 10.2 so their devices wouldn’t be impacted by the power management feature Apple introduced in iOS 11.2 for iPhone and iPhone 7 Plus. However, some users have reported that though they were able to downgrade to an older version successfully, they were not able to activate their devices.
It is not clear what caused the older iOS versions to be signed again, but it is possible that it was due to a bug. Apple stops signing older iOS versions, so users cannot downgrade down to a jailbreakable iOS version. Apple has used this strategy to keep jailbreakers at bay. It not only releases new software updates, that fixes the vulnerabilities used by the jailbreaks, it also stops signing the older iOS firmware file, which prevents users from downgrading back to the older iOS version that can be jailbroken.
Were you one of the lucky people to downgrade your iPhone to a jailbreakable iOS version? Let us know in the comments.