Stuxnet has been called the most sophisticated computer worm ever created. We know there are siblings to the malware which took down Iran’s nuclear centrifuges, but now Kaspersky labs is saying there may be up to four other worms in the family tree.
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Raiu said the platform is comprised of a group of compatible software modules designed to fit together, each with different functions. Its developers can build new cyber weapons by simply adding and removing modules.
"It's like a Lego set. You can assemble the components into anything: a robot or a house or a tank," he said.
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Though we don’t know what lab the worms originated from, the same one gave birth to both Stuxnet and Duqu as well as the three siblings. Kaspersky discovered this after observing the two virus’ attempt to find the other three. Costin Raiu, the firm’s director of global research and analysis, explained that when the two are deployed, they search for registry keys that allow them to fully install their malware. When searching for those keys, however, Kaspersky found Stuxnet and Duqu were both searching for three other keys. This means that the worms have siblings that work in tandem with it, strengthening its damaging power.
http://www.reuters.com/article/2011/12/29/us-cybersecurity-stuxnet-idUS…
http://venturebeat.com/2011/12/29/stuxnet-siblings/