Korea's prosecution said Tuesday that a cyber attack from North Korea was the cause of the worst-ever crash of a South Korean banking network last month, raising alarms about a new type of cyber attack against private financial firms.
"An unprecedented act of cyber terror in which North Korea is involved" caused the weeks-long paralysis of the banking system of South Korea's agricultural cooperative, Nonghyup, said Kim Young-dae, a senior prosecutor from the Seoul Central Prosecutors' Office in charge of the investigation.
The prosecution said it found that the method used in the April 12 attack of the banking network is similar to one used by North Korea for a series of cyber attacks on key South Korean government and business Web sites in 2009 and in March this year.
One of the Internet Protocol addresses used to break into the Nonghyup network was identical to one used two months ago for the distributed denial-of-service (DDoS) attack that originated from North Korea, it said.
Prosecutors said that a laptop owned by an employee of IBM Korea, the cooperative's computer network maintenance subcontractor, became a zombie computer after downloading North Korea's hacking programs, disguised as update files, from a file storage site in September 2010.
The Pyongyang-hired hackers leaked secret information on Nonghyup's computer network system while closely monitoring the laptop for the next seven months through the implanted programs, they said. The hackers then conducted the cyber attack on April 12, the investigators said.
Kim said that once the programs penetrated Nonghyup's computer system, they encoded malicious codes and files and hid their tracks, just as in the two previous DDoS attacks.
The prosecution said that the incident is a new type of cyber terrorism that targets one private firm in an effort to destroy the financial foundation of South Korea's capitalist society. (Yonhap)