SEOUL: A fresh wave of cyber attacks that slowed US and Republic of Korea (ROK) websites this week hit more targets on Thursday, a Web security firm said, while the ROK's spy agency has said the hacking may be linked to the Democratic People's Republic of Korea (DPRK).
The impact of the attacks, aimed so far at dozens of sites including the White House and the ROK's presidential office, was seen as negligible, experts said.
"The anticipated attack did take place, but considerable counter-measures were taken and it did act as a defense to some degree," an official at the online security firm Ahnlab said.
Some government websites, including the defense ministry and the National Intelligence Service, were affected. Access to some US government sites, including the State and Defense departments, from the ROK appeared to be disabled.
Banks act quickly
The Internet sites of some ROK banks also experienced a surge in access requests but a bank official said programs were run to disperse traffic and bring service back up within an hour.
One online expert was quoted as telling an ROK daily that tracking of the spread of the malicious software showed it had originated from an IP address based in the US.
The attacks saturated target websites with access requests generated by malicious software planted on personal computers. This has overwhelmed some targeted sites and slowed server response to legitimate traffic.
More funds for defense
The attacks did not lead to a breach of sensitive government material or damage online infrastructure in the ROK, the world's most wired country, government officials said.
But the National Intelligence Service said in a statement it was stepping up alert to monitor potential attack against the network of energy and communications facilities.
The defense ministry is allocating 26 billion won ($20.33 million) to beef up security for its computer system, according to a budget request it released yesterday.
An expert on Pyongyang at the Heritage Foundation, Bruce Klingner, said the DPRK had in operation a military unit with up to 1,000 skilled computer hackers created 10 years ago.
Last month, the DPRK issued a warning about a possible "high-tech war" against the ROK for spreading what it described as false information about its involvement in cyber attacks.