Ransomware is an emerging threat in the evolution of cybercriminals techniques to part you from your money. The latest variant of the infamous ransomware Cryptolocker is targeting users by forcing them to download the malicious software by through advertising on the high profile domains belonging to Disney, Facebook, The Guardian newspaper and others. The service where users are instructed to pay the ransom amount is a hidden service that uses the Command-and-Control server hosted on TOR.onion domain. Cisco has noticed high levels of traffic consistent with the new “RIG” exploit kit, thereby blocking requests to over 90 domains.
Source: https://thehackernews.com/2014/06/new-cryptowall-ransomware-spreading.html