A police agency in South Korea has found that North Korean hackers were responsible for cyber attacks on two South Korean firms that resulted in the theft of at least 40,000 defense-related files, The Wall Street Journal reported Monday.
A spokesman for Hanjin Group’s subsidiary Korean Air Lines Co. said the stolen files included designs for the wings of an F-15 fighter aircraft and pictures of parts of unmanned reconnaissance planes, the newspaper reported.
A military official in South Korea said the stolen documents were not classified and “will likely have a negligible impact on national security,” according to the report.
“North Korea turns out to have been preparing for a long time to try to launch a countrywide cyber attack,” the South Korean police agency said.
North Korea’s cyber hacking campaign was detected in February and compromised over 140,000 computers at 160 government agencies and companies in South Korea, the report said.
A spokesman for SK Holdings said the cyber attack affected four of its group affiliates.
Police officials told Reuters they traced the hack to an internet protocol address based in Pyongyang, North Korea, that zeroed in on network management software used by government agencies and private firms.
They also found that the IP address was similar to the one used in a 2013 cyber attack on computer networks of South Korean banks and broadcast stations, Kim reports.