The administration panel was first discovered by Trend Micro researchers last week, who obtained a sample of version 1.3.05 of the SpyEye builder. Loucif Kharouni, senior threat researcher with Trend Micro, says the sample his team has -- basically a work-in-progress beta -- includes some lines of Zeus code, but it's not really 50-50 Zeus and SpyEye at this point.
Researchers have been eagerly awaiting such samples of the merged two malware packages since "Slavik" or "Monstr," the author of Zeus, gave the source code to another crimeware author, "Gribodemon," a.k.a. "Harderman."
Aviv Raff, CTO of Seculert, whose firm has also studied the new malware toolkit, says the final version of the merged Zeus-SpyEye trojan is likely to be a mutation of both pieces of malware. "Because of that, cybercriminals who are used to the bluish interface of Zeus panel will find it easier to migrate from older versions of ZeuS to the new merged version," Raff says.
The merged toolkit obtained by Seculert includes both SpyEye- and Zeus-like administration panels, both linked to the same back-end database with the same botnet data. And the bots' naming conventions are just like that of SpyEye, according to Seculert's research. Stolen certificate files from botnet victims were stored SpyEye-style, in the database, not as files on the server like Zeus does.
"The core of the merged version seems to be, indeed, SpyEye, with additional layers and features of ZeuS," Raff says. It gives the cybercriminal the "flexibility" to choose old and new features from the two Trojan kits, he says.
And it's a powerful combination. While Zeus was able to remove some security applications, SpyEye was not: Now the merged version can do so, he notes. Plus Zeus' relative user-friendliness made it popular. "Zeus is the 'king of botnets' mainly because of its ease of use," he says. "The merge was probably done mostly because of that."
Trend Micro's Kharouni says this version of the crimeware toolkit is more "private" in that it's not being widely distributed. "We are probably seeing some leaked version," he says. "The way the author is providing this version is completely different: He's only sending it to specific customers he knows."
Kharouni says Trend Micro has seen about 10 servers running this version of the Trojan so far.
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