‘Restricted mode in iOS 11.4.1 can be circumvented with cheap accessories’

Researchers from the company Elcomsoft, which focuses on iOS security, among other things, claim that it is possible to circumvent the so-called USB restricted mode with cheap accessories. Apple introduced USB restricted mode in iOS 11.4.1.

The company writes that based on its own testing, it found that it is possible to reset the restricted mode timer by connecting an untrusted Lightning accessory. So it does not have to be connected to the relevant iPhone before. The cheapest accessory that currently allows that is a Lightning camera adapter that costs about $40. The researchers also want to test whether the work-around works with other, cheaper accessories.

For law enforcement, this would mean that a seized iPhone should be connected to such an accessory as soon as possible, after which it should be connected to a power bank and placed in a Faraday bag. That would prevent the restricted mode timer from expiring. An important condition is that restricted mode is not yet enabled when the phone is seized. If that is the case, then it makes no sense to reset the timer.

Apple introduced restricted mode Monday in version 11.4.1 of iOS. This restricted mode means that if the device has not been unlocked for more than an hour, the lightning port will no longer accept data connections without unlocking the phone first. As a result, the port can only be used for charging the iPhone.

It is speculated that Apple introduced the mode to prevent the use of cracking tools, which are connected to the lightning port. Apple says the mode is not intended to antagonize government services. There have been rumors before that the makers of those tools had managed to circumvent restricted mode.