Apple has quickly corrected a mistake that allowed iPhone, iPad, and iPod touch users to downgrade to older software versions on early Thursday.
The situation began on late Wednesday when Apple suddenly stopped signing all iOS versions for select devices, including the iPhone 4s and some very old iPad and iPod touch models, according to the website IPSW.me.
Next, it appears that when Apple went to flip the switch back on, it accidentally began signing several older software versions between iOS 6 and iOS 11.1.2 for any compatible iPhone, iPad, and iPod touch models.
Not entirely sure why the signing window has opened for iOS 6–10 [...]
Apple has stopped signing iOS 9.3.5 for compatible iPhone, iPad, and iPod touch models, effectively ending iOS 9 downgrades.
iOS 10.0.1 is also no longer being signed, making iOS 10.0.2 the oldest software update users can still downgrade their devices to via iTunes.
Apple routinely stops signing older software updates several weeks after they are released.
iOS 9.3.5 was released in late August as the last update to the iOS 9 operating system, with major security fixes for three zero-day exploits. iOS 10.0.1 was released on September 13 as the first iOS 10 version for all devices beyond the iPhone 7 and iPhone 7 Plus.
The move does not affect [...]