Ransomware is a type of malware that restricts access to the infected computer system in some way, and demands that the user pay a ransom to the malware operators to remove the restriction. The usual way one get infected is by open an email with an attachment. But now there is a new way.
Malvertising hits global news sites.
Some site on the internet including the NY Times, the BBC, AOL and a host of other major news and entertainment websites inadvertently ran malicious ads that attempted to hijack the computers of visitors and demand a ransom, according to security researchers Malwarebytes and Trend Micro.
Your best protection is to have a GOOD, Current Backup of your systems. Get and use a backup solution that you trust and then verify that you can restore your data.