A week after the April 1 deadline, it became clear that the people responsible for Conficker had strong financial motivations. The worm downloaded a well-known spam generator. In addition, computers infected with the worm also began to display a highly annoying “Windows Security Alert” pop-up warning every few minutes. The alerts claimed that the computer was infected with a virus, which was true enough. Yet these scareware warnings also promised that the only way to clean one’s machine was to download the $50 program advertised—credit-card payments only, please.
Ironically, routine updates could have prevented the worm’s spread in the first place. In fact, Conficker emerged a full four weeks after Microsoft released the “urgent” security patch that protected computers against it. Clearly, millions of machines were not being updated. And millions still probably are not properly immunized—a disturbing thought, considering that, even after its April actions, Conficker resumed waiting for further instructions.
Note: This article was originally published with the title, "Pulling Up Worms".