Again Apple’s iOS12 is subject to reveal secured data.
Yet the process is really complex and might need a
second phone as well as Siri being activated in the lock
screeen. Most users should hence be safe though!

As José Rodriguez shows in his video, you will most likely need a lot of tools activated in order to gain access to photos and contacts.

The first method involves Siri, VoiceOver, a second phone that can perform ougoing calls. The second phone also requires the Notes app.

Watch here: