A number of things are known about the Gauss Trojan first discovered by the folks at Kaspersky Lab in the fall of 2011. We know that it's closely related to Flame which was allegedly created by U.S. intelligence interests to attack Iran. We know that Gauss isn't attacking Iran, but instead seems to be snooping on computers and networks elsewhere in the Middle East.
We also know that Gauss can spread through USB memory sticks. We think we know that Gauss is targeting something or someone, but we don't know who or what. We know that Gauss installs a TrueType font, Palida Narrow on machines it has infected.
We have also learned that if it doesn't find what it's looking for, it deletes itself. We know that Gauss seems to target banking information from Lebanese financial institutions. We know that most of the infections are in Lebanon, Israel and the Palestinian territories.
Kaspersky Lab says in its report that the few infections found elsewhere, like the 43 found in the United States are probably on machines physically located in the Middle East and connected through a VPN. And finally we know that the servers controlling Gauss were shut down in July. So Gauss is probably not a significant threat at this time.
So what was Gauss up to? Despite the interest in banking information, Gauss is probably not being used to steal money. First of all, there haven't been indignant reports of money being stolen from interests in the Middle East. Second, Gauss is based on the Flame espionage software, meaning that it's probably engaged in espionage also.
So if it's true that Gauss is a state-sponsored malware package looking for banking information along with user data, passwords, personal data, social networking and the like in Lebanon and elsewhere, why was it doing it?
If I had to guess and it is only a guess, I'd say it's looking for terrorist organizations. A primary method of tracking terrorist groups has been the same for a long time and that is to follow the money. This would explain a lot. The U.S. has tracked down a number of terrorists, taken them into custody and awarded them free one-way trips to tropical Cuba. It's also used their financial and communications to present them with gifts, such as Hellfire Missiles sent from above. So tracking money and communications will net you some terrorists, if only you know whom to track.
It would appear that this is what Gauss was up to. It would explain the extraction of banking information (but not money), the recording of browser activity and the collecting of social media information. Terrorists don't generally communicate using Outlook to send email, after all. Instead, the common practice is to use the Web and to go to compromised sites or to sites with prearranged access and leave messages there. The collection of browsing history by Gauss would net that information as well.
So why did the control servers shut down in July? There are a couple of possibilities. Perhaps Gauss found the targets it was searching for and shut down to protect its anonymity. Perhaps the operators of Gauss realized they had been discovered and wanted to eliminate any chance of being tracked down. Perhaps it was a scheduled shutdown to minimize the risk of detection. In reality, nobody knows for sure.
And why does Gauss use the Palida Narrow font? Again, if I had to guess, I suspect that this is the way Gauss checks to see if it's already infected the machine. If it has, it doesn't do it again and instead erases itself to avoid detection. Gauss also erases itself from USB drives if it checks a machine and finds that it's not on the list of things to infect. For a piece of malware, Gauss seems to go to a lot of effort to erase itself and doesn't go to much trouble spreading itself.
In fact, the Kaspersky Lab report says that right now, it's not clear how Gauss spreads, but notes that it does not spread indiscriminatelyâanother non-malware trait. Now that the Gauss network seems to be rolling up, it's likely we'll never know for sure who sent it out or why it was sent. Critical portions of the code are encrypted with keys we don't have or don't know. We don't really know what was sent to the control servers before they were shut down.
The good news is that unless you're in the Middle East, the chances of any individual's personal machine being infected with this Trojan are vanishingly small. Even better, detection is easy as is removal. Your antivirus software almost certainly knows about it and will remove Gauss automatically. There's also a Kaspersky site you can visit that will tell you.
So this brings us to the final question. Now that Gauss has mysteriously disappeared, what's next? We don't have an answer to that, but since it was an espionage tool, chances are good that we won't know what's next until it's already over.