Chico Harlan and Ellen Nakashima
August 30, 2011
SEOUL — After nearly half of the servers for a South Korean bank crashed one day in April, investigators here found evidence indicating that they were dealing with a new kind of attack from an old rival: North Korea.
South Korean officials said that 30 million customers of the Nonghyup agricultural bank were unable to use ATMs or online services for several days and that key data were destroyed, making it the most serious of a series of incidents in recent months. But even more troubling was the prospect that a belligerent neighbor had acquired the tools to disrupt one of the world’s most heavily wired nations — and that even more damaging attacks could be in store.
“This was an unprecedented act of cyberterror involving North Korea,” said Kim Young-dae, a senior South Korean prosecutor in charge of the investigation.