Some versions of the mysterious MiniDuke malware discovered last year targeting European governments shared code with a Trojan tracing its origins back to the early years of the commercial Internet, a new analysis by Finnish firm F-Secure has found.
MiniDuke was odd from the start and not in a particularly threatening way. It wasn't sophisticated but then it probably didn't have to be to find a way around defences during the era it started out, around 2011. In those days, awareness of state-sponsored malware was low.
According to discoverer Kaspersky Lab, the malware's purpose was data and credential theft from its targets including Ukraine, Belgium, Portugal, Romania, the Czech Republic, Ireland, and Hungary, with a total of 23 countries affected. The list of organisations was low at only a few dozen and included NATO, raising immediate and valid suspicions of an attack by a state power.
Carrying out an analysis of MiniDuke, F-Secure's researchers noticed that some versions used a loader containing source code from a Trojan called Cosmu which has existed in a family of variants going back as far as 2001.
They decided to call this cross 'CosmicDuke' but what, if anything, does the strange commonality between two separate pieces of malware amount to?
Most likely, the fact that a piece of state-sponsored targeted cyber-weapon uses commercial code implies that the same people are behind both, perhaps as a piece of moonlighting. Which piece of malware is the moonlighting and which is the main business is harder to assess. In the most likely scenario, a group of professional malware writers created MiniDuke, re-using old code they'd worked on that had done its job well enough.
As F-Secure itself notices, the fact that the decoy document used to spread the malware as an attachment is 'Ukraine-Gas-Pipelines-Security-Report-March-2014.pdf' hints at the actor behind this attack. Beyond that nugget F-Secure won't say.
"At the moment, crimeware which targets consumers is under attack by international law enforcement. It is quite possible that the displaced crimeware vendors found a new buyer of information," speculated F-Secure security advisor, Sean Sullivan.
None of this is sophisticated. The software exploit in use dates hits a Flash vulnerability dating back to 2011 (CVE-2011-0611) most competent defenders would have patched ages ago and the re-use of source code is pretty slapdash. Stolen files are simply thrown out to at FTP servers that are still active, all pretty basic stuff 2011-era stuff.
The people who built Stuxnet and its ilk would roll their eyes at shortcuts like this.
Bizarrely, versions from this year even use a decoy file that appears to be an image of someone holding up a Russian receipt complete with embedded EXIF data identifying the phone model that took the it complete with the date.
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