Mastercard is feeling the wrath of the internet this afternoon - its website and at least part of its payment systems have apparently been brought down by a denial of service attack.
The credit card company is being typically cryptic - its most recent statement said only that it is "is experiencing heavy traffic on its external corporate website", which is a nicely understated way to describe an overwhelming DDoS assault.
The statement added: "We are working to restore normal speed of service. There is no impact whatsoever on our cardholders' ability to use their cards for secure transactions."
However the Reg has been contacted by merchants down under who are currently unable to access the payment portal on Mastercard's private network - a far more serious breach of security than just downing a website.
This blog also suggests that Mastercard's 3D Secure system is not working either.
The hack attack is being claimed by Operation Payback, as revenge for Mastercard's decision to shut down payments to Wikileaks in the wake of its publishing US diplomatic cables.
Operation Payback has itself come under DDoS attack from 'patriot' hackers. Presumably pro-Assange hackers have taken out Senator Lieberman's personal site.
PayPal was targeted for similar reasons, but was functioning at the time of writing.
Mastercard's PRs were unable to confirm any attack on payments systems but have promised us a more up-to-date statement. We'll update this story should we receive one. ®