Hackers threaten Greek banks with DDoS

Three Greek banks are being subject to extortion by cyber criminals who are threatening to disrupt online trading if a bitcoin ransom isn't paid today.

According to Greek news site Ekathimerini, the three unnamed banks were first contacted by the extortionists, calling themselves Armada Collective, on Thursday of last week. They demanded a ransom in Bitcoins from each of the banks, stating that if they were not paid by Monday 30 November a serious DDoS attack would begin.

The group or individual apparently proved they were capable and serious in their threat by briefly taking all three banks online services offline at the same time as issuing the threat.

Ekathimerini also reported (in Greek) that, while online banking may be disrupted, the banks' financial transaction systems are unaffected by the threat.

The publication added that a number of service providers are also increasing capacity for the banks to handle traffic in an attempt to thwart the attackers and a special taskforce made up of the Greek National Intelligence Service, Financial Crimes Squad and Bank of Greece has been put together to deal with the crisis. Financial journalist Yannis Koutsomitis has also claimed the FBI is involved, citing an anonymous source.

It has also been suggested Armada Collective tried to extort money from banks in Switzerland and Thailand over the past few weeks. However, neither these banks nor those in Greece have been named, allegedly to avoid panic.

This is a developing story and will be updated as more information comes in.