Jonathan Zdziarski has conducted different studies on the architecture of iOS discovering that different services are unnecessary for users and could be used to bypass security defenses. The file_relay tool can be accessed remotely or via USB to bypass the backup encryption, exploiting the feature an attacker can access all of the data encrypted via the data protection if the device has not been rebooted since the last time the user entered the PIN. HFSMeta creates a disk image of everything thats on the phone, not the content but the metadata on all files and all installed apps.”]
Source: https://securityaffairs.co/wordpress/26844/hacking/hidden-services-ios.html