No longer the province of teens and chat-obsessed netizens, instant messaging is being adopted by a growing number of banking malware applications, which zap pilfered credentials to thieves in real time.
The latest entrant is Zeus, a trojan that monitors an infected PC for passwords entered into banking websites and other financial services. Over the past three months, investigators from RSA FraudAction Research Lab have observed the program, which also goes by the name Torpig and Mebroot, using the Jabber IM protocol to make sure the most valuable credentials don't get lost in the shuffle.
The move signals the growing focus on immediacy among scammers as they try to counter the increased use of measures designed to detect and prevent banking fraud.
"One of the things that has definitely changed in recent times is that the half life of a stolen credential is decreasing," said Sean Brady, a senior manager for identity protection and verification at RSA, a division of EMC. "There is definitely a sense of urgency of the part of these fraudsters about using the credential."
Previously, Zeus uploaded the credentials to a drop server database, which scammers periodically checked. The new method employs PHP scripts that automatically send credentials as soon as they're intercepted. That allows thieves to retrieve the information much more quickly than would otherwise be possible. It also allows retrieval even when crooks, many of whom don't always have reliable net connections, don't have access to the server hosing the drop.
As a growing number of banks adopt the use of one-time passwords, the need for speedier delivery mechanisms is growing. Instant messaging makes it possible for thieves to thwart such measures by, in some cases, allowing them to silently make transactions while a victim is still logged in to an online bank. A competing trojan known as Sinowal has used similar methods since last year, RSA researchers said.
The IM scripts are highly customizable. RSA researchers observed one version of Zeus that IMed credentials for customers of a single US-based financial institution that was being targeted. In another case, the trojan sent dispatches for five pre-set institutions. (For convenience, it also emailed the information as well). ®