Verizon DBIR challenge clue #4

Ding! Ding!  We have a winner.   One participant has solved the cryptographic challenge in this year's Verizon Data Breach Incident Report (DBIR).   However, there are still second and third place cash prizes up for grabs.

Hopefully, this should be the last clue:

"If you've found the p(f+) in a fingerprint, you should be able to find the key."

Keep searching.