South Korea Computer Crash
Depositors leave after checking their accounts through automated teller machines of Shinhan Bank at a subway station as the bank's computer networks ...
Depositors leave after checking their accounts through automated teller machines of Shinhan Bank at a subway station as the bank's computer networks was paralyzed in Seoul, South Korea, Wednesday, March 20, 2013. Police and South Korean officials were investigating the simultaneous shutdown Wednesday of computer networks at several major broadcasters and banks. While the cause wasn't immediately clear, speculation centered on a possible North Korean cyberattack. (AP Photo/Ahn Young-joon)
South Korea Computer Crash
Employees of Korea Internet Security Center work after computer networks at two major South Korean banks and three top TV broadcasters went into shut...
Employees of Korea Internet Security Center work after computer networks at two major South Korean banks and three top TV broadcasters went into shutdown mode en masse, at a monitoring room in Seoul, South Korea, Wednesday, March 20, 2013. Police and South Korean officials investigating the shutdown said the cause was not immediately clear. But speculation centered on North Korea, with experts saying a cyberattack orchestrated by Pyongyang was likely to blame. (AP Photo/Yonhap, Han Jong-chan) Korea Out
APTOPIX South Korea Computer Crash
Two bank clerks, left, check an automated teller machine at a branch of Shinhan Bank after the bank's computer networks are fixed in Seoul, South Kor...
Two bank clerks, left, check an automated teller machine at a branch of Shinhan Bank after the bank's computer networks are fixed in Seoul, South Korea, Wednesday, March 20, 2013. Computers networks at two major South Korean banks and three top TV broadcasters went into shutdown mode en masse Wednesday, paralyzing bank machines across the country and prompting speculation of a cyberattack by North Korea. (AP Photo/Lee Jin-man)
APTOPIX South Korea Computer Crash
Depositors try to use automated teller machines of Shinhan Bank while the bank's computer networks are paralyzed at a subway station in Seoul, South ...
Depositors try to use automated teller machines of Shinhan Bank while the bank's computer networks are paralyzed at a subway station in Seoul, South Korea, Wednesday, March 20, 2013. Computer networks at two major South Korean banks and three top TV broadcasters went into shutdown mode en masse Wednesday, paralyzing bank machines across the country and prompting speculation of a cyberattack by North Korea. (AP Photo/Ahn Young-joon)
APTOPIX South Korea Computer Crash
A depositor leaves after checking his account through an automated teller machine at a subway station as the bank's computer networks was paralyzed i...
A depositor leaves after checking his account through an automated teller machine at a subway station as the bank's computer networks was paralyzed in Seoul, South Korea, Wednesday, March 20, 2013. Police and South Korean officials were investigating the simultaneous shutdown Wednesday of computer networks at several major broadcasters and banks. While the cause wasn't immediately clear, speculation centered on a possible North Korean cyberattack. (AP Photo/Ahn Young-joon)
South Korea says an initial investigation shows a Chinese Internet address was the source of a cyberattack on one of the companies shut down by computer crashes.
South Korea's telecom regulator said Thursday that a Chinese address created the malicious code in the server of one of the banks, Nonghyup, that crashed Wednesday.
Experts say hackers often launch attacks via computers in other countries in an attempt to keep their identities from being exposed. Such addresses can easily be manipulated and disguised.
Regulators have distributed vaccine software to government offices, banks, hospitals and other institutions to prevent more outages.
The source of the attack is not yet clear. But suspicion has quickly fallen on North Korea. Pyongyang has threatened Seoul with attack in recent days.
