When Zotob and other worms attacked a Windows vulnerability in August, some (yeah, that's me) were surprised that large companies were affected. After all, even a simple firewall should have blocked the attack. The problem was that many large corporate networks aren't as controlled as you'd think.

The most common explanation is of remote users and notebooks taken out of the office, infected outside the corporate LAN, and then brought back in either physically or through a VPN, there to dirty-up everyone else.

Everyone knows a lot of this goes on, but you'll also find rogue access points and other policy cheats that end up compromising security.

The link for this article located at eWeek is no longer available.