The attack was apparently launched a day or two before Christmas. Interestingly, the botnet behind the attack was a variant of the Zeus botnet, known as Kneber, which downloads a Perl script -- converted to an executable file -- that trolls for and copies documents to a server located in Belarus.
Security blogger Brian Krebs gained access to the server used in the attack, and found two gigabytes of PDFs, Word, and Excel documents, apparently from dozens of victims. Among the agencies that fell victim to the attack were the National Science Foundation's Office of Cyber Infrastructure; the Massachusetts State Police; the Moroccan government's Ministry of Industry, Commerce and New Technologies; and the intergovernmental Financial Action Task Force.
Kneber was first seen in February 2010, when security firm NetWitness estimated that the botnet had infected 75,000 PCs, many belonging to government agencies. At the time, the security firm reported that less than 10% of antivirus software were able to spot the advanced attack, and that no intrusion detection systems spotted the malware's peer-to-peer communications component.
Both appearances of Kneber have targeted not just government secrets, but also financial data, including "sites such as eBay, MySpace, and Microsoft, as well as online-payment processors, PayPal, and e-gold," said Alex Cox, principal research analyst for NetWitness, in a blog post.
Cox said the new version of Kneber appeared to be the work of the same attacker, as an analysis of the attack code found that two of the executables and three of the domain names were quite similar to the previous attack, and that the malware code itself was nearly identical in size.
As before, the malware searches for state secrets, as well as banking information and useful Web site credentials. "This evidence shows the continuing convergence of cyber-crime and cyber-espionage activities, and how they occasionally mirror or play off one another," said Cox.
But the attacker's backing or intent remains unclear. "Who is the end consumer of this information?" he asked.