Romanian antivirus company BitDefender warns for cybercriminals sending out emails with malicious help-files containing the Crypto Wall ransomware. The emails contain a .CHM file (Microsoft Compressed HTML Help) as attachment. CHM the successor of the famous .HLP help files in Windows.
The concerned emails occur as email messages from a fax machine. Once the ransomware becomes active it starts to encrypt files on the computer rendering them useless. In order to decrypt the files, the victim has to pay a ransom. According to Bitdefender the cybercriminals distributing the ransomware are currently mainly targeting businesses. The last couple of months several companies have reported to have become a victim of the malware.