Bot-net tracker group Shadowserver noticed a gigantic drop in infected systems on Christmas day. the total number dropped from more than 500,000 to less than 400,000, or more than 20%. Another independent group confirmed a 10% drop on their numbers. What's the deal?
Well, interestingly enough, the combination of people getting newly purchased, XP Service Pack 2 PCs (or Macs), combined with machines not being turned on for the holidays and people being away from work, made the number of infected PCs decrease dramatically. We wouldn't expect the numbers to stay lower for long, however. Once grandma starts browsing those hardcore porn sites again, she can add her new machine to the bot-net once more.
Bot-infected PCs get a refresh [Security Focus]