‘KeRanger’ is the first fully functional, native OS X ransomware designed to infect and forcibly encrypt Apple OS X systems, researchers warn. The malware, dubbed KeRanger, first appeared March 4, disguised as an RTF document inside installers for a popular BitTorrent client called Transmission. Once it gets installed, the ransomware is set to begin encrypting all files – including Time Machine backups – after three days. It then demands 1 bitcoin – currently worth about $400 – in exchange for an encryption key.”]
Source: https://www.govinfosecurity.com/alert-ransomware-targets-macs-a-8948