One of the variant’s driver files was signed with a valid digital certificate that expires August 2, 2012. The digital certificate belongs to a company headquartered in Taipei, Taiwan. The certificate was revoked on October 14, 2011.

Duqu uses HTTP and HTTPS to communicate with a command-and-control (C&C) server that at the time of writing is still operational. The attackers were able to download additional executables through the C&C server, including an infostealer that can perform actions such as enumerating the network, recording keystrokes, and gathering system information.