With over half a million users, Signal is an incredibly secure cross-platform instant messaging app. With emphasis on security, there is no wonder that Signal is frequently picked as a communication tool by those who have something to hide. Elcomsoft Phone Viewer can now decrypt Signal databases extracted from the iPhone via physical (well, file system) acquisition, and that was a tough nut to crack.
The Screen Time passcode (known as the Restrictions passcode in previous versions of iOS) is a separate 4-digit passcode designed to secure changes to the device settings and the user’s Apple ID account and to enforce the Content & Privacy Restrictions. You can add the Screen Time passcode when activating Screen Time on a child’s device or if you want to add an extra layer of security to your own device.
By this time, seemingly everyone has published an article or two about Apple re-introducing the vulnerability that was patched in the previous version of iOS. The vulnerability was made into a known exploit, which in turn was used to jailbreak iOS 12.2 (and most previous versions). We’ll look at it from the point of view of a forensic expert.
What can and what cannot be done with an iOS device using Touch ID/Face ID authentication as opposed to knowing the passcode? The differences are huge. For the sake of simplicity, we’ll only cover iOS 12 and 13. If you just want a quick summary, scroll down to the end of the article for a table.