With hardware-backed full-disk encryption and additional protection of sensitive user data located in the keychain, Apple iOS is the most secure mobile operating system out there. Acquisition approaches that are traditional for Android and Windows Phone devices (namely, JTAG, ISP and chip-off) are completely meaningless for iOS devices running even years-old generations of the system. Bypassing screen lock password (passcode) has also been long considered to be useless due to the fact user data stored in the keychain is additionally encrypted with a secure key based on the passcode.
While we can’t do much with the former, our recent research shows that the latter is not entirely true. Bypassing the passcode does reveal quite a bit of information that can be useful for an investigation. And this is not just a theoretical research. We are building this functionality into a ready-to-use commercial tool, iOS Forensic Toolkit, to allow extracting data from locked iDevices – providing they have a jailbreak installed. The tool will allow pull available information from devices locked with an unknown passcode. That includes devices that were powered on (or rebooted) and never unlocked. Naturally, a pre-installed jailbreak is required in order to access the data.