For the use of the Oracle Destination, a driver must be installed.

Xtract Universal Version 2.64.0 and higher (Released Nov. 5, 2015)

The Oracle Data Provider for .NET 4 (managed driver) must be installed. At the time of the documentation was 12c Release 4 (12.1.0.2.4) the newest version:
http://www.oracle.com/technetwork/database/windows/downloads/index-090165.html

You should follow the instructions to install the driver. On a 64-bit system you should install the 64-bit version of the driver, on a 32-bit system the 32-bit driver version.
You can also install alternatively the complete ODAC or the complete Oracle DB Client, if the ODP.NET component is selected.

You should download the latest version of the provider from the software vendor’s website.
Important: After the installation the Xtract Universal service must be restarted!

Prior to Xtract Universal Version 2.64.0 (of 24th. Nov. 2015)

The Driver “Oracle Data Provider for .NET 2.0” must be installed, which is part of the “Oracle Data Access Components (ODAC)”:

You should download the latest version of the provider from the software vendor’s website.
Important: After the installation the Xtract Universal service must be restarted!