A new malware called Locky has been discovered that encrypts data using AES encryption. The malware demands 0.5 to 1 bitcoin ($210$420) to decrypt files. Locky is currently being distributed via a phishing email that contains Word document attachments with malicious macros. An educated user would think twice before allowing the macro to run, but in some cases, the shell script run by the macro can be interpreted by security software as a malicious action. The immediate financial return is too good for cybercriminals to ignore.”]
Source: https://securityintelligence.com/news/locky-sends-you-an-invoice-and-makes-you-pay/