Romanian security company BitDefender today said it has traced the cyber-espionage malware "MiniDuke" back to June 2011, more than a year and a half before the campaign was uncovered.
BitDefender found the malware by digging through its detection logs, first finding a sample compiled and used by attackers in May 2012. Additional sweeps then identified an even earlier example of the malware dated June 2011.
The new findings significantly push back the start of the MiniDuke espionage campaign, and show that the group responsible spied for months before being revealed.
MiniDuke was publicized and analyzed last week by researchers from Moscow-based Kaspersky Lab and the Laboratory of Cryptography and System Security (CrySyS) at the Budapest University of Technology and Economics. The malware used rigged PDF documents to exploit a then-unpatched critical vulnerability in Adobe Reader.
Adobe fixed the flaw with an "out-of-band," or emergency, update issued Feb. 20.
The June 2011 version of MiniDuke was written by the same group that created the more recent samples analyzed by Kaspersky and CrySyS, said Stoica Matei Razvan, a communications specialist with BitDefender Labs, in an interview today.
"Much of the code is the same," said Razvan of BitDefender's comparisons of the June 2011, May 2012 and February 2013 versions. "It's the same group."
Like the most recent run, the May 2012 MiniDuke was implanted on victims' machines using malicious PDFs posing as invitations to a conference. "The organization is real and the contacts listed in the PDF are real," said Razvan. "The PDF looks just right, but it's a fake."
The May 2012 campaign also exploited a then-unpatched flaw in Adobe Reader, Razvan confirmed. Adobe patched Reader three times in 2012: in January, April and August.
The security firm also found hints in the May 2012 copy of MiniDuke of Chinese involvement: It pinged the time-server.org website for the current time and date in China.
Even so, Razvan declined to attribute MiniDuke to Chinese hackers, saying that the time and date request could be a red herring planted by the malware's makers.
When MiniDuke was first revealed, security experts argued over its origin, with some pointing to China while others blamed hackers in Eastern Europe, perhaps from Russia or countries that had once been part of the Soviet Union.
Romania's secret service has claimed that MiniDuke was state sponsored, but has not identified the nation it believes was behind the attacks that were aimed at NATO (North Atlantic Treaty Organization), a slew of organizations in Europe, and in the U.S., several prominent research institutes and think tanks.
Like Kaspersky researchers last week, Razvan today characterized MiniDuke as less ambitious than Stuxnet or Flame, but still sophisticated. "Compared to Stuxnet or Flame, which were really big software projects backed by lots of money, MiniDuke was probably created by a smaller team," said Razvan. "Its code is not as modular, not as complex."
Razvan also said that a Twitter account used to provide command-and-control instructions to MiniDuke was still active, although its latest message was posted Feb. 21. That account was previously used to backtrack possible MiniDuke activity to April 2012.
BitDefender has released a MiniDuke removal tool, which can be downloaded free of charge from its website.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed. His email address is [email protected].
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