Apple's next iOS update, iOS 11.4, is currently in beta testing and Elcomsoft has discovered a major security update within it that will likely pose problems for law enforcement agencies. The new security feature, called USB Restricted Mode, will disable to Lightning connector of an iPhone or iPad if the device hasn't been unlocked within seven days. 

The Lightning connector can still be used for charging, but no data can be extracted from the iOS device. However, if the owner of the iPhone or iPad unlocks it using a passcode, the Lighting port will reactivate. The feature was first seen in the iOS 11.3 beta, but was never officially released, so there's still a chance it won't be ready for the full iOS 11.4 rollout. 

Apple's official notes for the feature say: "To improve security, for a locked iOS device to communicate with USB accessories you must connect an accessory via lightning connector to the device while unlocked – or enter your device passcode while connected – at least once a week."

Elcomsoft has tested the feature, but still hasn't figured out if the Lightning port disables only if the device isn't unlocked with a passcode for seven days, if it isn't unlocked at all using a passcode or biometrics, or if the device hasn't been unlocked or connected to a trusted computer. In their testing, Elcomsoft didn't try to unlock the iOS device at all, or connect it to a trusted computer and the port disabled.

This means that if law enforcement agencies need to obtain information from an iPhone or iPad, they will have a much smaller window of time in which to unlock it. It should also mean services such as GreyKey won't be able to get into them either. GreyKey uses the Lightning port to install a piece of software that can figure out the passcode of an iOS device. GreyShift, the company behind GreyKey, keeps its unlocking methods under tight lock, so Apple doesn't know how it works.