Cyber-attacks paralyzed three major banks and three largest TV broadcasters in South Korea on March 20, shutting down the computer networks of Shinhan Bank, Nonghyup Bank, Jeju Bank, KBS, MBC and YTN. Seoul suspects North Korea's involvement because the shutdown came five days after Pyongyang accused South Korea and the United States of cyber-attacks and threatened to retaliate.
The cyber-attacks on South Korea are more sophisticated and better coordinated in using malware to start destroying operating systems (OS) simultaneously regardless of OS types — Windows or Unix — than previous distributed denial-of-service (DDoS) attacks.
Fortunately disruptions to the banks' operations were relatively short term, and the South Korean media outlets were able to continue broadcasting. Yet, the incident demonstrated that perpetrators can target critical infrastructure and cripple their functions at least partially and temporarily.