hankyoreh

The presidential office Cheong Wa Dae said Tuesday that some computer networks of its National Security Council (NSC) offices came under attack from computer viruses, suspected of being part of a hacking scheme, in February, resulting in the leak of some unclassified documents.

In a press release, Cheong Wa Dae said it has confirmed signs of a "worm" virus attack occurring within the NSC computer networks in the middle of February, when Lee's predecessor, Roh Moo-hyun, was serving as president.

As a result of the virus attack, some unclassified personal data belonging to NSC personnel were leaked and the authorities are now taking measures to discipline the staff members responsible for the unprecedented incident, Cheong Wa Dae said.

"Signs of worm virus attacks were detected within the NSC networks after Cheong Wa Dae and relevant government agencies had in early March conducted a comprehensive security check on the presidential office's computer networks transferred from the Roh government," said the press release.

"At that time, the attacks were blocked by Cheong Wa Dae's firewall. The virus attack and document leak may have been caused by mistakes by some NSC officials. A follow-up probe is now under way to punish all responsible for the incident," it noted. A computer worm is a program which copies itself across a network mainly through e-mails.

President Lee Myung-bak was inaugurated on Feb. 25. Lee once complained that his personal computers at Cheong Wa Dae office buildings and residence were paralyzed for over 10 days after his inauguration.

Informed sources at Cheong Wa Dae also said a group of unidentified PC users, suspected of being hackers, had attempted to gain access to the presidential office's computer networks over the weekend, when Lee was traveling in the U.S. for a Camp David summit with U.S. President George W. Bush.

"We cannot determine for certain whether the latest virus attack was a hacking attempt or not. But Cheong Wa Dae takes the latest virus attack particularly seriously, as the NSC is the presidential office's key security-related organization dealing with the nation's top classified data and intelligence," said a presidential aide.

SEOUL, April 22 (Yonhap)