McAfee Labs has closely monitored the activity around the ransomware WannaCry. Many sources have reported on this attack and its behavior, including this post by McAfee’s Raj Samani and Christiaan Beek and this post by Steve Grobman. In the last 24 hours, we have learned more about this malware. These findings mainly concern the malware’s network propagation, Bitcoin activity, and differences in observed variants.

https://securingtomorrow.mcafee.com/mcafee-labs/analysis-wannacry-ransomware/