There’s plenty of blame to go around for WannaCry (a.k.a. Wcry, Wanna Decryptor), the ransomware that hit more than 200,000 organizations in 150 countries. Let’s focus on a driver behind this malware campaign that hasn't been widely discussed: complexity.
WannaCry encrypted files on Windows computers in hospitals, train stations, shipping hubs, automotive manufacturing plants and power companies (among others), then demanded a ransom - payable in BitCoin - to unlock the files on the victim’s PC.
Once delivered to a Windows machine, this ransomware exploits a security hole in the file transfer protocol used in Microsoft networks. For in-depth information, I recommend the Wcry US-CERT Alert and Everything you need to know about the WannaCry / Wcry / WannaCrypt ransomware on Troy Hunt’s blog.
Who’s behind it? We still don’t know. As for who’s to blame, let the finger pointing begin: