Hackers attempt to disrupt presidential office, foreign ministry, intelligence agency and US military websites, Seoul says

This article is more than 9 years old

This article is more than 9 years old

Hackers have attacked about 40 South Korean government and private websites, prompting officials to warn of a substantial threat to the country's computers.

The country's National Cyber Security Centre said it had seen signs of a "denial-of-service" attack, in which large numbers of computers try to connect to a site at the same time in an attempt to overwhelm the server.

A South Korean cyber security company, AhnLab, said in a statement the targets included websites belonging to South Korea's presidential office, the foreign ministry, the national intelligence service, US Forces Korea and major financial institutions.

South Korea's media regulation agency, the Korea Communication Commission, said no immediate damage to the websites had been reported.

AhnLab spokesman Park Kun-woo said the attacks were similar to others in the past, in that they were denial-of-service attacks and largely targeted the same sites.

AhnLab said a computer user discovered a bug in their system on Thursday. After analysing it, AhnLab found malicious software designed to attack websites and warned the targets in advance so that they could prepare. As a result, Park said, there had only been a brief slowing of some of the websites.

Government officials have said that previous denial-of-service attacks on South Korean government websites were traced to China. It was not immediately clear from where Friday's attack originated.

Park said people often point to China as the source of such attacks because a large amount of malware originates from there. Malware is malicious software designed to access a computer without the owner's consent.

Cyber attacks on South Korea in 2009 were blamed initially on North Korea, but experts later said they had no conclusive evidence that Pyongyang was responsible.

South Korean media have previously reported that North Korea runs an internet warfare unit aimed at hacking into US and South Korean military networks to gather information and disrupt service.