Unfortunately a "Bump key" can open any lock. I have a secondary lock device to thwart it's use. Downside is, you can't get in yourself from outside. It's designed to protect you INSIDE.
When my father used to rent a small bungalow for us in the summertime, both doors had a skeleton key only...bet those are really easy to break into these days.
Shallow drilled locks are bump proof, as are programmable slide bars like BiLock. Any lock that does not contain springs is also invulnerable to bumping, as long as they don't have a key backup.