The Blaster Worm: Then and Now

In August of 2003 the Blaster worm struck the Internet, infecting at least 100,000 Microsoft Windows systems and causing millions of dollars in damages. In spite of considerable cleanup efforts, an antiworm aimed at patching systems, and a widely downloaded clean-up tool from Microsoft, the worm is still very much alive. In this article we describe observations of the Blaster worm from its onset in 2003 to its continued persistence a year later.