Oracle Privilege Analysis Now Free in EE from 18c and back ported to all 12c
The license details for 18c are here.
I wrote an article back in 2015 and also did a webinar for SANS and Oracle on a practical walk-through of Database Vault and Oracle 12c and this included using and testing Privilege Analysis. You can read about that here.
Great news; nice to see security features no longer being cost options. This is good to have; privilege analysis and reduction of privileges to least rights is also key to a super-locked Oracle database.