
I have no explanation that I am sure of.
I think you don't either.
My guess is a security hole, a bug.
Your guess is an inherent deficiency of architecture.
Neither of us is in a position to prove our guesses. You are in a somewhat better position to investigate - you actually have logs and what not from your co-worker's breakage. But, unless you understand _exactly_ how the malware gained access to the protected areas of the system, we still don't know for sure.
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And what are we doing when the two most powerful nations on earth -- America and Israel -- stomp on the elementary rights of human beings?
-- letter to the editor from W. Ostermeier, Liechtenstein