Chinese hackers have reportedly targeted South Korean businesses and that country's government over the Terminal High-Altitude Area Defense System, also known as THAAD. The cyberattacks are apparently in response to the deployment of a THAAD battery to South Korea.
According to The Wall Street Journal, the American cyber-security firm FireEye claims that a series of attacks on South Korean business and government computer networks may be related to the deployment of the ballistic-missile defense system. The groups responsible for the attack, APT10 and Tonto Team, are believed to be tied to the Peoples Liberation Army.
The attacks are also being carried out by so-called "patriotic hackers" like the Panda Intelligence Bureau and the Denounce Lotte Group. The latter hacking ring is targeting a South Korean conglomerate that has permitted the deployment of THAAD on some land it owned. Lotte Group was subjected to a denial-of-service attack on an online duty-free store after the approval was announced in March 2017. South Korea's Ministry of Foreign Affairs was also targeted by a DOS attack at that time.
China has long opposed the deployment of THAAD to South Korea, claiming such a deployment would undermine China's ballistic missile capabilities. China has a large number of ballistic missiles in its inventory, many of which are medium or intermediate-range systems.
According to a March 1, 2017, report by RT, Russia and China agreed to work together to strengthen opposition to the BMD system's deployment. The Chinese government's official response to the South Korean hosting of THAAD included halting a real-estate deal and barring some South Korean celebrities from entering the country.
The THAAD battery, consisting of six launchers that each hold eight missiles along with assorted support vehicles, was deployed to South Korea to counter the threat posed by North Korea's ballistic missiles. According to Army-Technology.com, the system has a range of at least 200 kilometers (124 miles), and is able to hit targets almost 500,000 feet above ground level (ArmyRecognition.com credits THAAD with a range of 1,000 kilometers – equivalent to over 600 miles).