There will be only one patch this month on Microsoft patch day next Tuesday, although it is critical and a worm could take advantage of it without user action.

In August, Microsoft released six updates on Patch Tuesday, and hackers wasted no time in targeting one of the problems they fixed. Within days, a number of different worm attacks that exploited a bug in the Windows Plug and Play service began taking down an estimated 250,000 computers, primarily Windows 2000 systems being run in corporate environments.

When a large number of patches get released, companies can spend the entire month testing the new software to make sure it works with their existing applications, but with only one bug to be patched this month, things should be much easier, said Steve Manzuik, a product manager with eEye.

"I think September will be quiet," Manzuik said. "When we get the six, seven, eight or nine patches, it gets to be a bit more difficult."