FBI's Internet Crime Complaint Center's (IC3) data shows CryptoWall as the most current and significant Ransomware affecting millions of individuals and businesses in US.
CryptoWall and its variants have been targeting people since April 2014, between April 2014 and June 2015, the IC3 received 992 CryptoWall related complaints, with victims reporting losses totaling over $18 million.
The victims incurs ransom fees between $200 and $10,000, there are additional costs which includes network mitigation, network countermeasures, loss of productivity, legal fees, IT services, and/or the purchase of credit monitoring services for employees or customers.
The system becomes infected when the victim visits or clicks on the infected advertisement, email, attachment or infected websites- The malware encrypts the victim's file stored on the infected machine. Ransomware schemes demand payment in Bitcoin as it is easy to use, fast, publicly available, decentralized, and provides a sense of heightened security/anonymity.
Victims can register the complaint to local FBI field office, or may also file a complaint with the IC3 at www.IC3.gov.