China accused as major hack exposes details of up to 35m South Koreans

South Korea is reeling from what could be the country's biggest ever data breach after it was revealed that the personal details of as many as 35 million web users may have been hacked.

South Korean web firm SK Communications said in a statement on Thursday seen by The Korea Herald that the personal details of 35 million users of its Nate online portal and Cyworld social network had been compromised.

It is thought that the details include phone numbers, email addresses and names, sparking fears that large-scale phishing and spam campaigns could soon be targeted at South Korean citizens. Resident registration numbers and account passwords, however, were encrypted.

SK Communications claimed that the hacking originated in China, although this has yet to be substantiated by police, according to the report.

Mark Darvill, director of security firm AEP Networks, said that it has become increasingly difficult to differentiate between politically and financially motivated attacks targeting everything from military to civilian, financial or critical infrastructure systems.

"All organisations involved in the critical infrastructure of a country need to ensure that they are co-ordinated within the country they serve through initiatives such as the UK National Cyber Security Programme, and that they deploy the absolute highest level of security available to them," he added.

"This is not only to protect assets and internal sensitive data, but to guarantee that national security is in no way compromised by individuals, groups or politically motivated government-backed organisations."