A humorous and glowing example of this is Pfizer, who has found themselves victim of spambots. The company, better known as the manufacturer of Viagra, has found their own inboxes flooded with spam for their own products. The reason is that machines on their internal network have become compromised by hackers on the outside and turned into spambots, churning out tons of email.
This had negative effects on the company, such as their own IPs being blacklisted:
Wesson says Pfizer computers have been spamming inboxes for the last six months and that he's kept 600 spam messages sent from company computers. He says 138 different Pfizer IP addresses have been blacklisted by various groups, but adds that he can't estimate the number of infected machines without more information or installing monitoring equipment on the edge of Pfizer's networks.
And apparently this is not unusual. The article brings out an unnamed company as an example, that ended up having around 2,500 machines infected by something. What makes this story particularly funny is the apparent obliviousness to the problem. How common is this? Are even workstations inside a private network easily capable of being just as annoying as the multitude of infected PCs in the great wide open? While I don't think they are truly unaware of it, it is a sign of how lax security policies or perhaps understaffed IT can have an affect not only on a company, but the Internet as a whole.