O’Murchu estimated it took at least three teams to code all of Stuxnet—an elite, highly skilled tiger team that worked on the payload that targeted the Siemens software and PLCs; a second-tier team responsible for the spreading and installation mechanisms that also unlocked the payload; and a third team, the least skilled of the bunch, that set up the command-and-control servers and handled the encryption and protocol for Stuxnet’s communication.
