A keylogger was discovered on the system of one of the victims together with the main module described above. The main module is very similar to Stuxnet both in structure and in behavior. However, the name Duqu has almost no connection with it. This name is based on the names of the files that are related to a completely different malicious spy-program! This second malicious program, which is basically a. different malicious. program, Duqu, was given the name of the main. module based on these files.
Source: https://threatpost.com/mystery-duqu-102011/75778/