N.Korea Hacks into Secret War Plans

North Korean hackers seem to have managed to access a secret war masterplan by South Korea and the U.S. in a cyberattack last September, sources here said Monday.

One government source said Defense Ministry investigators questioned around 40 people over the hacking attack and it appears that part of the masterplan, dubbed OPLAN 5027, "leaked." A Defense Ministry source said the hackers accessed reports containing portions of the plan, not the entire document.

Defense Minister Han Min-koo and other military officials last year downplayed the seriousness of the hacking attack, saying that only a small number of sensitive military secrets leaked out.

OPLAN 5027 was first drawn up in 1978, when the South Korea-U.S. Combined Forces Command was established, and updated every two years since 1994. It includes troop deployment plans, key North Korean targets, strategies and military control of facilities in the North.

A military official said "discussions are still taking place" whether the plan has to be overhauled now the North has seen chunks of it. 

The ministry found out about the leak while investigating a new computer virus in September that attacked the vaccine server at the military cyber command.

Investigators discovered that the Defense Ministry's Internet and Intranet servers were infected with the same malware, affecting the minister's own computer and around 2,500 computers with Internet access and 700 connected to the Intranet.

At the time, the ministry said only that hackers accessed "some military information, including sensitive information" and that North Korea appears to be responsible.

The hackers tried to attack the main server of the Defense Integrated Data Center, which serves as the cyber nerve center of South Korea's defense system.