The malware paralyzed computers in factories, banks, government agencies and transport systems, hitting 200,000 victims in more than 150 countries by Monday. It also hit a "limited number" of U.S. companies over the weekend, a senior DHS official confirmed to Fox News. CERT (Computer Emergency Readiness Team) worked with the affected U.S. companies and their European partners over the weekend to get a patch to parties affected by the ransomware infection.

Though many first heard about WannaCry on Friday, Microsoft discovered it earlier this year and released a security update to patch the hole in its system on March 14, Brad Smith, Microsoft's president and chief legal officer, said in a blog post on the company site. 

SOURCE FOXNEWS.COM