Details on Cyber-Attack on U.S., South Korea Emerge

As security researchers work to break down the malicious code tied to a DDOS attack targeting government and commercial sites in the United States and South Korea, more information is leaking out on how the attack happened. Still, much about the attacks-including the motives and identity of attackers-remains unknown.

More details are surfacing about a massive denial-of-service attack that has hit both government and commercial Websites in the United States and South Korea in the past few days.

According to security researchers, the attacks are the work of malware that infected users and routed traffic to government and commercial sites starting during the July 4 weekend. Just what that Trojan is exactly is the subject of some disagreement, with some researchers contending the malware is an updated version of the infamous MyDoom worm that plagued Windows users in 2004. However, connections between MyDoom and the malware involved in the attack may be overplayed, according to Joe Stewart, director of malware research for SecureWorks' Counter Threat Unit.

"It's definitely not an updated version of MyDoom," he said in an interview. "I'm not really seeing all that many similarities...most of the code seems to be unique."

Stewart could not say how the malware is being spread. But what is clear is the attack is even broader than initially reported. On July 5, the list of sites to be attacked included only five U.S. government sites. By the following day, however, that featured 21 sites, including some in the private sector. On the 7th, the list was updated again and had 26 sites, including some in South Korea.

Among the sites hit by the attack were the U.S. Department of Treasury, the White House, the Federal Trade Commission and the Washington Post. Some of the organizations are reported to have fended off the attacks.

At the moment, the motives of the attackers remain unclear. No data was stolen, and it appears that the only impact was the takedown of some high-profile sites.

"I am a little suspicious over the timing of this attack," said Rick Howard, the director of iDefense Security Intelligence. "We are still not clear about the purpose or motivation. The target list is somewhat unique in that iDefense has not seen these organizations lumped together like this in the past. As the Obama administration tries to come to grips with the new cyber-security policy, this event will be highlighted on the front of their radar screens. My question is this: who would most benefit from an attack like this now?"

Stewart speculated the attackers may have been after attention.

"Most of the DDOS botnets we see are written by people that are doing this for profit, and there doesn't seem to be a profit motive for this one. It's just sending a lot of traffic... to try and flood [the sites]," he said.

So far, Stewart said his analysis of the code has not found any conclusive proof about the origin of the attack.

"There's a few strings here, there's the word China, and then there's the Korean language type that they are using in the Web requests that they're sending to the attacked site, but anybody can put that in there to throw you off the trail," he said. "That doesn't say anything to me conclusively at all."

However, according to the Associated Press, South Korea's National Intelligence Service told South Korean lawmakers July 7 that North Korea or its sympathizers were behind the attack. If so, it would not be the first time hacktivism brought down government Websites. Just last year, for example, attackers defaced Lithuanian government and commercial Websites with anti-Lithuanian rhetoric and a communist hammer and sickle symbol.

Among the South Korean Websites affected were the presidential Blue House and the Defense Ministry, as well as some banking sites.