Hi,
Read this article (https://shivabizint.wordpress.com/2012/05/03/how-are-credentials-stored-in-obiee-11g-and-weblogic-infrastructure/ ) that says the AD principal password is encrypted in the config.xml file using AES algorithm. Does anyone know if it's using 128 or 256 bit encryption? Couldn't find documentation that confirms it...
with no guarantee of the answer I saw once a reference to 128-bit AES in a doc about OPSS and credential store.
This document might be of some help to you. It describes in some detail the supported encryption algorithms.
Oracle confirmed it's using AES 128 bit.