Kaspersky experts were called to investigate Duqu and they discovered that its framework was written in a programming language they didn’t recognize. The mystery of the unknown programming language is solved. Duqu framework is (most likely) written in an custom object-oriented extension of the programming language C called “OO C”. That code it is compiled with Microsoft Visual Studio Compiler 2008 with some special options (“/O1″ and “/Ob1″) that optimizes the code size and the inline expansion. Despite the fact that it is a malicious software, the developers have done an excellent job and they make the life of security expert difficult.

Duqu’s secret programming language