Conficker

Windows worm whose millions of drones and domain-generation trickery forced an industry-wide posse.

Core Principles & Analysis

• From late 2008 it built a botnet estimated at nine to fifteen million machines.
• Its domain-generation algorithm minted hundreds of rendezvous domains daily to dodge takedowns.
• Microsoft posted a $250,000 bounty; the Conficker Working Group united rivals against it.