Worth a read:
My only question is why would the dropper care whether it's running in a virtual environment? A bit more digging reveals that the malware author is assuming that if his code ends up running in a VM, it's probably a sandbox and being studied, so the malicious code refuses to co-operate. Clever.
Here's the analysis of Cryptowall 2.0, from the same blog:
This wonderful turbine-powered car should have won at Pebble Beach - But why didn't the world's most beautiful car win best in show?
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