Researcher traces 'Gameover' malware to maker of Zeus

Computerworld - The "Gameover" malware that the FBI warned users about earlier this month is a preview of the next version of the even-more-notorious Zeus money-stealing Trojan, a security researcher said today.

"Gameover represents the latest and greatest source code package from the Zeus author," said Don Jackson, senior security researcher with Dell SecureWorks' counter-threat unit. "[New features] in Gameover will be rolled into the final Zeus version 3, which is in beta and will wrap up soon if it hasn't already."

Two weeks ago, the FBI warned of increased action by Gameover, including rounds of spam that tried to dupe recipients into infecting their PCs with the malware, which like Zeus, is designed to pillage individuals' and companies' bank accounts.

Jackson, who has been tracking the Zeus malware and its developer for years, said that Gameover posed a new and more dangerous threat because it had been created by the maker of Zeus specifically at the behest of one of his biggest clients.

"The crew using Gameover has requested a lot of changes in the Zeus functionality," said Jackson, adding that the hacker crew using Gameover has direct access to Zeus' maker because it pays him well and often for support.

"The Zeus author now has only three or four major clients," said Jackson. The criminal coder abandoned all his "small fish" to focus on supporting a handful of customers who pay top dollar for his work.

Almost a year ago, Zeus's creator halted development after the software's source code leaked to the Internet. Subsequently, other security researchers noticed that many of Zeus' features were rolled into another crimeware construction kit called SpyEye. Last August, experts at Moscow-based Kaspersky Lab highlighted a botnet dubbed "Ice IX" that was reportedly built atop the older Zeus source code.

Jackson believes that the maker of Zeus decided to turn those events to his advantage.

"He dumped all his small fishes," said Jackson, "which not only takes the heat off him, but also removes him from resellers. It lets him concentrate and focus on what would be next for Zeus."

The additions demanded by the Gameover gang, which the Zeus developer quickly created, included a new, more distributed form of command-and-control (C&C) that uses a peer-to-peer function to update infected machines when or if a botnet's single C&C server is discovered by authorities and taken offline.

Gameover, which Jackson said should be considered a "private version" of Zeus, also supports the use of complex Web injections that allow criminals to bypass multi-factor authentication now used by many financial institutions to stymie account plundering.

And the crew apparently asked for changes to Zeus that would let the gang rent third-party botnets that specialize in conducting distributed denial-of-service (DDoS) attacks, Jackson added.