User = "staff"

This post was prompted by noticing, on a MAC external library setup in my new MyCloud Home, a user “staff” with read-write access. I understand this is a normal group on OSX, and nothing to do with WD staff - it just replicates from the privileges on the internal iTunes library which I copied there.

But I’m worried. I’m new to the MyCloud Home product and concept, and I get it’s merit.
But you essentially need to trust WD that the information you put on the internet facing external drive is secure - both from WD itself and potential outside attach. I’d like to understand what those security measures are. Are there any nicely summarised documents specifically about this?