Apple has stopped signing iOS 12.5.5 firmware and closed the verification channel. Users can no longer downgrade or revert to iOS 12.5.5 via iTunes or Finder after upgrading their iPhone, iPad and iPod touch software.
Last September, Apple pushed the iOS 12.5.5 update (internal version number: 16H62) to iPhone and iPad users for older iPhones and iPads that are unable to run iOS 15. According to Apple’s release notes, this is a security update that fixes vulnerabilities in CoreGraphics, WebKit, and XNU.
Earlier this September, Apple released the iOS 12.5.6 (internal version number: 16H71) update for older iPhones and iPods, which provides security updates and bug fixes for devices that cannot be updated to iOS 15. This is Apple’s first update to iOS 12 since September 2021.
The following devices cannot be upgraded for iOS 15 and iPad 15 and later.
- iPhone 5s
- iPhone 6
- iPhone 6 Plus
- iPod touch 6
- The first generation iPad Air
- iPad mini 2
- iPad mini 3
