For a few weeks Patrick Gray has been saying he has a source(s?) that claim there is a viable attack involving pulling the NAND from the phone, reprogramming it

For a few weeks Patrick Gray has been saying he has a source(s?) that claim there is a viable attack involving pulling the NAND from the phone, reprogramming it offline and reattaching. We'll have to see if the reverse engineers are able to reproduce and publish, but between this and my overall security cynicism, I lean towards there being a way in but wouldn't be surprised that if the intelligence agencies have it, they're legit not sharing.