The Zeus Trojan, malware long known to steal banking credentials to siphon off victims' funds, has been spotted being put to yet another devious use: swiping business data from Salesforce.com.
Zeus malware was detected targeting an individual's Windows-based computer in order to get into Saleforce.com as the victim logged in, then quickly gathered up a large amount of Salesforce business data through a kind of web-crawling action, according to Adallom, whose cloud-based security-monitoring service spotted the ongoing attack on one of its customers.
"It grabbed 2 gigabytes of data in less than 10 minutes," explains Vice President of Marketing Tal Klein, noting it's the first time the company has seen a variant of Zeus being put to this kind of use.
A cyber-criminal had apparently taken readily-available Zeus code and attached a crawler to it, according to Adallom, which is sharing its findings with Salesforce. In theory, Zeus could be retrofitted to crawl over other types of software-as-a-service applications as well.
Zeus is the top banking Trojan, according to Dell SecureWorks, which made major discoveries about criminally-operated botnets based on the malware that date back to 2007. Arbor Networks recently put forward an analysis of one botnet version, Gameover Zeus, whose toolkit dates to 2011. Zeus is often described as sophisticated banking Trojan malware that can execute an array of financially-oriented attacks, such as grabbing online credentials and siphoning off funds in payment systems to enrich attackers running complex botnet operations that often involve "money mules" as well.
According to the recent Dell SecureWorks report, "Top Banking Botnets of 2013," Zeus banking Trojan variants accounted for about half of all banking malware seen in 2013. SecureWorks points out that Zeus is now being used not just to attack financial institutions but also stock trading, social-networking and e-mail services, plus portals for entertainment or dating, for example.
Attackers now appear to also be putting Zeus to use against Salesforce.com and possibly other SaaS applications in a type of attack that Adallom refers to as "land-mining" and "rolladexing" to grab loads of business data and customer information.
Adallom, whose service doesn't rely on agent software but looks at cloud traffic, detected the Zeus-related activity because of the unusual amount of traffic being downloaded from Salesforce to the victim's computer.
It was a highly targeted attack on an individual's home PC, and a specimen of the Zeus variant was seized off it, according to Adallom, which says an investigation is ongoing about it. The security firm can offer no answers as to where the attackers are or what they intend to do with the Salesforce data they're grabbing.