Armada Collective group has carried out three attacks in five days and is demanding 20,000 Bitcoin from each bank
Greece may be about to suffer another hit to its financial system after hackers carried out their third attack on the country’s main banks in five days.
Three Greek banks have been targeted by a group calling itself the Armada Collective, which is demanding a ransom of 20,000 Bitcoin (around £4.8m) from each or it will take down their websites.
Greek police and the country’s central bank have confirmed that the attacks took place, and say they have strengthened defences in preparation for further attacks.
The initial attacks, which began last Thursday, were distributed denial of service (DDoS) attacks, which crashed the bank’s websites by bombarding them with access requests.
The attacks succeeded in disrupting electronic transactions at all three banks for a short period, but customer information was protected, a police official said.
“No bank responded to this extortion, so the same hackers tried again at the weekend and today,” the official added. “But we had strengthened our defence in the meantime, so no disruptions took place.”
The computer systems of the affected banks are now being monitored by experts from the Greek central bank and the police electronic crime unit, a central bank official added.
“These kind of threats should be handled full force by authorities up the point where individuals involved in the activity are apprehended and indicted,” said Amichai Shulman, CTO of security firm Imperva.
“I’m not suggesting that banks and other organisations do not take any measures to protect their data assets and online presence (much like I don’t suggest people to stop locking their doors). However, this must not be the end game for handling cyber security threats. Putting the right DDoS protection in place is just the first line of defense that must be followed by authorities taking actions against offenders.”
A report from security firm Kaspersky found that DDoS attacks are becoming longer and more thorough as criminals specifically target certain organisations known to have weaknesses in their systems.
This included one attack which lasted for an astonishing 320 hours, as although more than 90 percent of attacks lasted less than 24 hours, the number of attacks lasting over 150 hours also grew significantly.
Bitcoin has also come under an increasing amount of scrutiny in recent times as its popularity continues to grow online, partly due to its use as a backbone for institutions such as the Silk Road, which have led to several run-ins with law enforcement services in the past.
The Bank of England also raised its suspicions about the use of Bitcoin last year, warning that the digital currency could pose a threat to financial stability in the UK should it see widespread adoption.
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