Zotob Worms Can Affect XP Computers

Microsoft admitted that the Zotob worm and similar worms could also affect certain Windows XP computers in a security advisory issued on Tuesday. Computers running XP Service Pack 1 with a certain configuration were at risk.

Previously it was thought that only Windows 2000 systems were vulnerable to Zotob-like attacks.

Windows XP machines with file and printer sharing, as well as the guest account enabled, would be vulnerable to the worm. Also, the computer could not be connected to a network domain, which means in most cases a home environment rather than a business network.

Microsoft urges all users to ensure they have applied all the necessary security patches issued earlier in the month.

Zotob, while not as destructive as past worms, still made its presence known last week by hitting several news networks, including CNN who broke into regular programming to announce its computers were under attack and constantly rebooting.

The worm copies itself into the Windows System folder and modified a user's "hosts" file to prevent access to antivirus Web sites. The worm also initiates an FTP server on port 3333 and scans IP addresses using port 445 for other vulnerable systems.

A patch for the problem was issued by Microsoft earlier this month.