I'm still knew to Lock Picking, so I've been looking around at different training material. I was looking at books on amazon and i saw "Keys to the Kingdom: Impressioning, Privilege Escalation, Bumping, and Other Key-Based Attacks Against Physical Locks" by Deviant Ollam. Obviously, this book is beyond my current level, but part of the title confused me.
My question, in simple terms, what is "Privilege Escalation" in regard to physical keys? I do Tech Support for my day job, so I'm very familiar with Privilege Escalation in regard to computer hacking. But I can't picture a way to do that with a physical key. Can someone explain please?