Here’s an article from Symantec (makers of Symantec Endpoint Protection) about the randomware attack hitting large organizations around the world.
Petya has been in existence since 2016. It differs from typical ransomware as it doesn’t just encrypt files, it also overwrites and encrypts the master boot record (MBR).
Symantec Endpoint Protection will protect computers against Petya. More generally, offsite backups are the best way to mitigate the effects of ransomware. Contact us if you would like to learn more about how to protect your company against ransomware or other malicious threats.