I guess my curiosity is how they got in.
Did they ram through some pretty complex cyber security protocols or did they figure out some low level employees password because it was "password."
Or was there a virus planted?
I think I could send North Korea a password protected excel spreadsheet and it wouldn't be worth their time to hack it.
There isn't a lot of forensic information out yet, but from what I have read, Malware is the most likely culprit. A piece of Malware planted in one or more servers, that obtained administrative access and spread via Windowns Management Instrumentation to a number of servers. The Malware had hard coded ip addresses of servers within the Sony network, which means the hackers had been researching the sony network for a siginificant period of time, and customized the malware for the Sony network. The amount of data they said they obtained was in the neighborhood of 100 Terabytes, of which about 40GB has been released (including some new movies).
Here is what I am reading in case you are interested.