On Christmas day, the number of bots tracked by the Shadowserver group dropped nearly 20 percent.
The dramatic decrease in weekly totals--from more than 500,000 infected systems to less than 400,000 computers--puzzled researchers. The Internet Storm Center, a threat monitoring group managed by the SANS Institute, confirmed a drop of about 10 percent.
One of the Internet Storm Center's network monitoring volunteers posited that the decrease was due to the large number of computers given as gifts this Christmas. The systems running Microsoft Windows XP will be using Service Pack 2, which also means the firewall will be on by default, adding an additional hurdle for bot herder looking to reclaim their drones.
"Many of the infected machines are turned off, the new shiny ones have not been infected, and the Internet is momentarily a safer place," Marcus Sachs, director of the ISC, stated in a diary entry. "But like you said, give it a few weeks and we'll be right back to where we started from."
Bots and bot nets have rapidly emerged as one of the major threats on the Internet. Tens of thousands of compromised PCs are frequently counted among a single bot net's unwilling members, with some bot nets boasting as many as a million systems. Traditionally, the networks have been used to install adware on victims' machines or level denial-of-service attacks at online companies as part of an extortion scheme.
Posted by: Robert Lemos