I think the key to this is looking at motives, since there must surely only be a small amount of possible motives for making such an attack - for example:

• Disgruntled member(s) of the team wanting revenge.
• Team member bribed by outside agency for reasons either known or unknown to them. (perhaps large corporations wanting to stifle growth of competing open source technologies).
• Direct attack by outside hackers for their own reasons.

I'm sure all of this will have been considered, but having come from a background where I have seen first hand the criminal extent to which 'world leading corporations' will go to stifle dissent and crush those they consider to be 'competitors' in some way - I just wanted to add that in to be clear!

May Utopian be reborn stronger and better than ever!