Windows Worm Hits Nine Million PCs

Here's a lesson in why it's important to keep up to date with patches, particularly on Windows machines. The Downadup worm infected 9 million PCs within four days last week. A patch released by Microsoft in October for MS08-067 hasn't been installed on a third of Windows systems, according to InfoWorld.

The patch would have supposedly protected against the attack from having been so widespread. Here are some details about the original vulnerability, when it was uncovered last October.