U.S. eyes N. Korea for ‘massive’ cyber attacks

The Korea Information Security Agency also attributed the attacks to denial of service.

Yang Moo-jin, a professor at Seoul's University of North Korean Studies, said he doubts whether the impoverished North has the capability to knock down the Web sites.

But Hong Hyun-ik, an analyst at the Sejong Institute think tank, said the attack could have been done by either North Korea or China, saying he "heard North Korea has been working hard to hack into" South Korean networks.

N. Korean sympathizers behind attacks?
On Wednesday, the National Intelligence Service told a group of South Korean lawmakers it believes that North Korea or North Korean sympathizers "were behind" the attacks, according to an aide to one of lawmakers who was briefed on the information.

An aide to another lawmaker who was briefed also said the NIS suspects North Korea or its followers were responsible.

The aides spoke to The AP on condition of anonymity and refused to allow the names of the lawmakers they work for to be published, citing the classified nature of the information.

Both aides told The AP that the information was delivered in writing to lawmakers who serve on the National Assembly's intelligence committee. The National Intelligence Service — South Korea's main spy agency — declined to confirm the information.

South Korea's Yonhap news agency said military intelligence officers were looking at the possibility that the attack may have been committed by North Korean hackers and pro-North Korea forces in South Korea. South Korea's Defense Ministry said it could not confirm the report.

Stewart said the attack software contained few clues about its origins, although a line of text deep in within the malware carried the cryptic message "get/china/dns."

Attack ‘thoroughly’ prepared
Earlier Wednesday, South Korea's NIS said in a statement that 12,000 computers in South Korea and 8,000 computers overseas had been infected and used for the cyber attack.

The agency said it believed the attack was "thoroughly" prepared and committed by hackers "at the level of a certain organization or state." It said it was cooperating with the American investigators to examine the case.

The outages were caused by so-called denial of service attacks in which floods of computers all try to connect to a single site at the same time, overwhelming the server that handles the traffic, the Korea Information Security Agency said.

In South Korea, 12 sites were initially attacked Tuesday, followed by attacks Wednesday on 10 others, including those of government offices, banks, vaccine firms and Web portals, agency official Shin Hwa-su said.

South Korean media reported in May that North Korea was running a cyber warfare unit that tries to hack into U.S. and South Korean military networks to gather confidential information and disrupt service.

INTERACTIVE Hack attack Learn how a denial-of-service attack works.

An initial investigation in South Korea found that many personal computers were infected with a virus program ordering them to visit major official Web sites in South Korea and the United States at the same time, Korean information agency official Shin Hwa-su said. There has been no immediate reports of similar cyber attack in other Asian countries.

Yonhap said that prosecutors have found some of the cyber attacks on the South Korean sites were accessed from overseas. Yonhap, citing an unnamed prosecution official, said the cyber attack used a method common to Chinese hackers.

Prosecutors were not immediately available for comment.

Shin, the Information Security Agency official, said the initial probe had not yet uncovered evidence about where the cyber outages originated. Police also said they had not discovered where the outages originated. Police officer Jeong Seok-hwa said that could take several days.

Some of the South Korean sites remained unstable or inaccessible Wednesday. The site of the presidential Blue House could be accessed, but those for the Defense Ministry, the ruling Grand National Party and the National Assembly could not.

Ahn said there were no immediate reports of financial damage or leaking of confidential national information. The alleged attacks appeared aimed only at paralyzing Web sites, she said.

South Korea's Defense Ministry and Blue House said that there has been no leak of any documents.

So could the North have carried out such an attack — or hired others to do it?

“That is very possible because those attacks are not very complicated,” said Andre Rickardsson, an information technology security expert at Sweden’s Bitsec Consulting. “North Korea is a country that sends up rockets and builds nuclear weapons, so why not build a virus? It’s not difficult.”

Paul Cornish, director of the International Security Program at the Chatham House think tank in London, agreed. “You don’t need to amass great armies, it can all be done covertly and cheaply,” by hiring outside expertise, he said.

Difficult to document
Documenting cyber attacks against government sites is difficult, and depends heavily on how agencies characterize an incident and how successful or damaging it is.

Government officials routinely say their computers are probed millions of times a day, with many of those being scans that don't trigger any problems. In a June report, the congressional Government Accountability Office said federal agencies reported more than 16,000 threats or incidents last year, roughly three times the amount in 2007. Most of those involved unauthorized access to the system, violations of computer use policies or investigations into potentially harmful incidents.

The Homeland Security Department, meanwhile, says there were 5,499 known breaches of U.S. government computers in 2008, up from 3,928 the previous year, and just 2,172 in 2006.

Peter Sommer, an expert on cyber-terrorism at the London School of Economics, cautioned against coming to quick conclusions as to who may have been behind the attacks, as any instigator would disguise where the attacks were coming from.

“Initial diagnoses are often wrong,” he said.

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