Oğuzhan Varsak

Oğuzhan Varsak


How Apple Completely Prevented Users from Downgrading iOS

Part 1

Long time ago, Apple allowed firmware updates while offline, this make it impossible for them to control the firmware version on these devices.

After canceling this feature (in the early days), iOS devices will connect to an Apple server, send their device information, and through “signed” firmware, the devices receives a Digital Signature in order to upgrade their device.

Continue reading