Worm #4: The message “Oops, your important files are encrypted.” or “Hello, dear friend! All you files have been ENCRYPTED.” displays on your screen and a ransom is demanded.
Visiting Geeks: These are classified as ransomware. Some computers at the City of Atlanta, Baltimore’s 911 system and Boeing were all attacked recently with a crypto-virus derived from a vulnerability uncovered by the NSA. This type of malware is classified as a WORM. Once a computer is infected, this WORM will seek out other computers on the same local network and try to infect them as well. Phishing is the typical way of gaining entry. Data is encrypted and cannot be recovered unless ransom is paid. To protect your computer, be vigilant on incoming emails, apply latest Microsoft security updates as well as having a real-time anti-virus protection, plus a off-site/cloud backup for your data.