14 companies report 'WannaCry' damage in Korea

South Korea's state-run cybersecurity agency said Wednesday that 14 companies have been struck by the crippling ransomware "WannaCry" so far, which has been emerging as one of the biggest threats to global cybersecurity.

Ransomware refers to malware that locks up files on a computer with encryption until the victims pay a certain amount of money to hackers. The latest instance of ransomware, called "WannaCry," first surfaced last week, damaging some 200,000 computers in 150 countries around the globe.