My girlfriends work computer was hit with Cryptowall 4.0 today. Since the computer belongs to the university she works for, the only backup is the useless sync to the university servers that only works when it rains and there's a full moon. Also, since she's not admin on it, I couldn't install a proper backup solution or a proper AV (Microsoft Security Essentials says everything is fine after a 5 hour full scan, despite a million encrypted files and a dozen popups at startup about paying to have them unlocked).
I'll dd the HD tomorrow and see if the shadow files are of any use (if they're still there), but best bet for now is the manual backup to external HD that she's been doing every week or so.
Well, at least she might be convinced to abandon Windows.