SEOUL, South Korea – Officials in several Asian countries said they feared a virus-like computer infection that disrupted Internet services worldwide over the weekend may cause more problems Monday.
"We believe the problem is hiding, not fully resolved," South Korean Information and Communication Minister Lee Sang-chul said Sunday.
"We cannot rule out the possibility of another attack when all businesses open tomorrow [Monday] morning," he said after an emergency meeting with computer experts.
Leung Siu-cheung, a senior consultant at the government-funded Hong Kong Computer Emergency Response Team Coordination Center, said the center had received at least five reports on Sunday about the virus attack, and expected more to come on Monday.
"Many people are not working on the weekend and they may not know that their computers at work have been infected," Leung said. "We expect more people will report on Monday."
Bharti Broadband Ltd., the Internet provider in India's capital, New Delhi, said Sunday that numerous customers had complained they were unable to log on to the Internet over the past 24 hours.
"We've received many complaints, but we've explained to our customers that it's a global problem with a virus affecting servers and choking the global bandwidth," said Priyanka Mathur, a spokeswoman for the company.
On Saturday, millions of South Korean Internet users were inconvenienced when some computers at Internet service providers Korea Telecom Freetel and SK Telecom failed to function, halting or slowing Web browsing and e-mail services.
Similar outages or slowdowns were reported in Thailand and Japan. The attack appeared to strike first in the United States and spread quickly, hitting Asia especially hard.
Lee said the disruption was caused by a so-called computer worm that created excessive Internet traffic, forcing domain servers to shut down in a chain reaction. He said most of the systems had been restored by noon Sunday.
The disruption affected busy weekend Internet banking and shopping traffic ahead of the Lunar New Year holiday on Feb. 1.
South Korea is one of the world's most computer-wired nations, with nearly two-thirds of its 46 million people having access to the Internet — many via high-speed broadband connections.
Officials in the United States said the attack sought out vulnerable computers on the Internet using a known flaw in popular software from Microsoft Corp. called "SQL Server." But the attacking software code was scanning for victim computers so randomly and so aggressively — sending out thousands of probes each second — that it overwhelmed many Internet data pipelines.