Computer networks at several South Korean banks and TV broadcasters crashed simultaneously early Wednesday. The attack paralysed ATMs across the country starting at 0520 GMT and they were still down six hours later.
South Korean officials sprang into action and set up a cyber crisis team, but it seems the large scale attack simply overwhelmed the infrastructure. Targets included Shinhan Bank, Nonghyup Bank, Munhwa Broadcasting Corp., YTN and Korea Broadcasting System.
Although nobody has claimed responsibility for the attack and South Korean officials are still not pointing fingers, most observers believe the attack was initiated by North Korea because, well, it's North Korea.
The malware used in the attack apparently wrecked computers, destroying their ability to reboot. Some operators reported seeing skulls on the screens before their imperialist machines went struck down by the righteous malware of reunification. Tech support clearly had a bad day, but some services were restored a few hours later
The attack is described as the biggest cyber onslaught against South Korea in more than two years. The fact that simultaneous, coordinated attacks were carried out points to an attacker with plenty of resources, such as a state sponsored group. North Korea is widely believed to have a rather capable cyber warfare unit created to hack US and South Korean networks.
The level of sophistication used in the attacks tends to be surprising, given the state of North Korea's economy and infrastructure. It is one thing to recruit hackers in the US, Europe or Japan, but finding suitable candidates in a country with virtually no internet and frequent power outages can't be easy.
However, it might be worth the effort. South Korea operates some of the fastest broadband networks on the planet and the economy is heavily dependent on broadband access. This also poses a massive security risk, as many facilities can be targeted by cyber attacks. A more serious attack could potentially wreak havoc on South Korea's 21st century infrastructure.
The South Korean military has also raised its cyber attacks readiness alert level, but it doesn't appear to have been targeted. The market didn't like the attack one bit and South Korean stocks tumbled, with the Kospi Index losing 1 percent. The won slid 0.5 percent.
In contrast, North Korea is practically Kim Jong-unhackable. Not because it has the best cyber security programme on the planet, or the wisest and greatest supreme leader, but because it has almost no internet infrastructure at all. Launching a cyber attack against North Korea would basically be like targeting an Amish community with an electromagnetic pulse weapon.