Hello,
The Informatica plugin connects to the DB. You can have Oracle 12c as your backend. You will need to make sure that you have appropriate JDBC driver for Oracle 12c. The JDBC for the database comes with the DB or it can be downloaded from Oracle here. If you experience any issues, then let us know.
For more details on the installation of the plugin, please refer to the documentation link here.
Thank you,
Nitin Pande
CA Technologies