In itself, a distributed denial of service, or DDoS, attack on a bank's website is little more than costly hooliganism. It essentially consists of hackers ordering a bunch of malware-infected computers to "click" on a bank's website until it's too overwhelmed to respond to legitimate users.
The effect is pretty similar to a barricade across the entrance to your bank: You can't get in, but your money is still safe inside the bank.
But what if thieves used a DDoS attack as cover for a more harmful attack that did actually compromise customer checking accounts? That appears to be exactly what happened to a customer of Bank of the West, according to a report from security blogger Brian Krebs:
A Christmas Eve cyber-attack against the website of a regional California financial institution helped to distract bank officials from an online account takeover against one of its clients, netting thieves more than $900,000.
At approximately midday on Dec. 24, 2012, organized cyber crooks began moving money out of corporate accounts belonging to Ascent Builders, a construction firm based in Sacramento, Calif. In short order, the company's financial institution -- San Francisco-based Bank of the West -- came under a large distributed denial of service (DDoS) attack …
There were 62 individuals suckered in to acting as "mules" for the stolen money, according to Krebs.
It's standard operating procedure for scammers to recruit unsuspecting individuals and businesses ("make big money working from home!") to accept a substantial deposit from thieves and wire the bulk of it overseas, keeping a portion for themselves as payments. Typically, the money clears and the mule completes the transfer, only to have the authorities catch up with them and claw back the money, leaving them on the hook for most of the losses.
Obviously, you never want to agree to accept and transfer cash as these mules did. Aside from the legal implications of engaging in what amounts to money laundering, what good are promised payoffs if they're going to be clawed back later?
Another important step to avoid having your account on the receiving end of this type of coordinated attack is having up-to-date antivirus software installed on your computer. Krebs writes that the thieves may have gained access to Ascent Builders' bank logins using malware surreptitiously installed on its computers. And you don't want that happen to you, especially on Christmas Eve.
What do you think? Do you worry about online thieves draining your accounts? What precautions do you take to prevent that from happening?
Follow me on Twitter: @claesbell.