By: Robert Lemos
A group of sophisticated online thieves have modified two popular attack toolkits to help them succeed in a global crime spree, stealing at least 60 million Euros-about $74 million U.S. dollars-from European and South American banks, security firms McAfee and Guardian Analytics stated in a June 26 report.
The widespread crime network showed that online thieves are increasingly using servers to automate many components of crime, such as providing information on active "money mules"-the people who receive stolen funds and, knowingly or not, launder them-and to automate the fraudulent transactions. The investigation, based on logs from more than 60 such machines, found that the criminals used the Zeus and SpyEye crime toolkits to steal 60 million Euros, but the damages could be much higher. Transactions totaling more than 1 billion Euros were attempted, but could not be confirmed completed, the report stated.
Moving the intelligence of the criminals operation out of the malware and into central servers has helped criminals steal money more efficiently, said David Marcus, director of advanced research and threat intelligence for McAfee. Each server handled an operation against a single financial institution or geographic area.
"If you go back a couple of years, most of the criminals' nastiness and heavy lifting happened on the end host," said Marcus. "What became really apparent here is this move to an automated transaction server methodology, and actually the vast percentage of the fraudulent logic to this server that is controlled by the fraudster, is making a difference. The amount of sophistication and how you can target specific individuals and specific financial institutions ... was astounding."
Dubbed "Operation High Roller" by the two firms, the crime ring targeted, in many cases, high net-worth individuals and companies that had more than 250,000 Euros in their accounts. Following the evidence, security researchers at the firms first found victims in Italy, then in Germany and the Netherlands. Digital bread crumbs later led to other operations in South America, where the thieves targeted businesses with more than $500,000 in the bank, and North America, where the thieves targeted 109 companies in the U.S. and Canada.
"We were able to identify the system-the communications between the infected hosts, the automated transaction servers and the command-and-controls servers," said Marcus. "The ones in Europe left the attack data exposed ... but the ones in America were locked down."
One of the two big advances demonstrated by the network is the increasing sophisticated criminal logic placed on servers that help automate fraudulent transactions. In the past, online thieves would be notified when the victim had logged into their bank account, and each theft of funds would have to be made manually.
Earlier in June, security firm Trend Micro identified the automated component, which it called an "automated transaction system" or ATS, as a threat to financial institutions. The investigation by McAfee and Guardian Analytics shows how that advance can be used to great effect.
In addition, the High Roller attack showed the criminals were getting better at hiding their activity on the victim's computer. Typically, a victim would log into their bank account, provide their code from a two-factor authentication token, and then see a "You are being logged in" message. Behind the scenes, however, the thieves were making a large transaction.
"From the bank's perspective, I just logged in, provided my credentials and made a transfer-that doesn't look fraudulent," said Marcus. "Without giving the bad guys too much credit, that's pretty clever."