October 01, 2010, 11:45 AM — The Zeus botnet remains a robust network that is difficult to destroy despite an international sting operation that saw dozens arrested this week for allegedly stealing money from online bank accounts.
Zeus is an advanced piece of malicious software that can intercept online banking details and initiate money transfers. It can infect computers that have software with coding flaws that have not been fixed.
Law enforcement officials arrested more than 100 people, mostly from Eastern Europe, in raids in the U.S. and U.K. this week on charges of money laundering, document fraud and conspiracy. The people were allegedly part of a large computer hacking money-laundering operation believed to have stolen more than US$260 million from businesses and consumers.
While it's encouraging to see law enforcement investigate, Zeus is still a problem, said Andre' M. Di Mino, a co-founder of the Shadowserver Foundation, an organization that tracks botnets.
"It's too early to determine or enumerate any key changes to Zeus itself," Di Mino said. "It remains fully operational and the security community continues to research and track it."
Victims can become infected with Zeus by visiting Web sites that are engineered to attack visitors' computers. Once those computers are infected, the attackers can siphon data and control the PCs using command-and-control (C&C) servers. Attackers often look for vulnerable Web sites in order to install the command-and-control software, which helps hide their tracks.
The arrests appear to not have had a significant technical impact on the Zeus botnet. As of Friday, at least 170 C&Cs for Zeus are still online, according to statistics compiled by the administrator of Zeus Tracker.
The statistics are updated three times a day and come from sources such as antivirus vendors, sandbox systems and other third-party sources, said the administrator of Zeus Tracker, who did not want to be identified.
The Zeus Tracker website records some of the most important information for those who are tracking Zeus-related websites, such as which ISP is hosting an infected domain and which registrar sold the domain name.
For a C&C server to be removed from the Internet, either one of three things must happen: the Zeus bot can be scrubbed from the computer by security software; the registrar can revoke the malicious domain name; or an ISP can take the offending server that is infected offline.