Microsoft is recommending that every Windows XP customer apply the patch immediately. Customers using Windows 98, Windows 98 Second Edition and Windows ME with the "Universal Plug and Play" service up and running should also use the patch, the company said.
Universal Plug and Play is Microsoft software that uses Internet protocols to allow devices such as computers, scanners and printers to automatically discover one another so they can communicate. Microsoft said an attacker who exploited the hole could take over computers on such a network.
Windows users can download the patch from Microsoft's Web site.
