Comment duqu definition in short (Score 3, Informative) 227
http://en.wikipedia.org/wiki/Duqu
Duqu is a computer worm discovered on 1 September 2011, thought to be related to the Stuxnet worm. The Laboratory of Cryptography and System Security (CrySyS) of the Budapest University of Technology and Economics in Hungary, which discovered the threat, analyzed the malware and wrote a 60-page report, naming the threat Duqu. Duqu got its name from the prefix "~DQ" it gives to the names of files it creates.
Symantec, based on the CrySyS report, continued the analysis of the threat, which it called "nearly identical to Stuxnet, but with a completely different purpose", and published a detailed technical paper on it with a cut-down version of the original lab report as an appendix. Symantec believes that Duqu was created by the same authors as Stuxnet, or that the authors had access to the source code of Stuxnet.
More likely Duqu==Stuxnet==Stars. Same guys, different vulns, different tools. Duqu is an instance made from a lego-kit.