More secure storage for mongodb credentials

Currently you can sort of "hide" S3 AWS credentials in core-site.xml, but for the mongodb connection the username and password are accessible from the Web UI, API, and ZooKeeper API because it is placed in the configuration for the storage plugin.

I wonder if it would be possible to store the username and password used for mongodb connection in a more secure manner, maybe it could be encrypted when you first save it, then even if you look at the configuration for the mongodb storage plugin via the ZooKeeper API you cannot extract the username and password.