South Korea Officially Blames North For Cyber Attacks

Tom Brewster is TechWeek Europe's Security Correspondent. He has also been named BT Information Security Journalist of the Year in 2012 and 2013.

South Korea officially blames its neighbour for outages at TV stations and banks

Seoul has stated North Korea was behind cyber attacks that saw a number of significant organisations knocked offline, as tension between the neighboring countries escalates.

Chun Kil-soo, an official at South Korea’s internet security agency, said there were similarities between a previous attack blamed on the North and those in March, including reused malware, according to AP.

Cyber attacks in South and North

On-line Piracy Key © bloomua - FotoliaA total of 76 pieces of malware were used in the March cyber attacks, which affected various banks and TV broadcasters. Chun said 30 of those were used in the previous attacks.

Security firm Symantec had previously discovered links between the 2011 distributed denial of service (DDoS) strikes on the South, which caused outages lasting for 10 days, and the most recent attacks. Both used a variant of a malicious program, known as Backdoor.Prioxer, and malware called Jokra, to allow attackers to compromise computers

It is believed the attack was carried out by a military spy agency, the Reconnaissance General Bureau, using six computers in North Korea, which routed their attacks through over 1,000 IP addresses in 40 different countries. The attacks were prepared over an eight month period, South Korea claimed.

“We saw evidence that the attack was extremely carefully prepared,” Chun added.

In March, North Korea claimed the US and South Korea had launched cyber attacks against a number of its organisations.

The claims came at a time of escalating aggressive rhetoric from the North, which said the peninsula was on the brink of nuclear war, advising foreigners to leave the South. Some Chinese travel agencies have already cancelled tourist trips to North Korea, according to reports.

Seoul has now raised its alert level to “vital threat”, in the belief the North is on the verge of launching a ballistic missile test.

There are fears the test will take place on Monday, the birthday of Kim Il-sung, the state’s late founder.

What do you know about Internet security? Find out with our quiz!