Duqu

They report that although both pieces of malware utilise broadly similar rootkit techniques, such as a kernel driver which first decrypts an encrypted DLL and then injects it into other processes,

http://www.h-online.com/security/news/item/Duqu-exploits-previously-unknown-vulnerability-in-Windows-kernel-1370369.html

May somone explain about this mechanism?

No one could answer me?