October is Cyber Security Awareness Month, which perhaps explains the generally poor state of computer security. We'd be far better off with Cyber Security Awareness Year, observed annually, all day, every day between January 1st and December 31st.

The problem is bots, malicious code that takes control of computers and gives it to someone else. Once a computer has been infiltrated by bot code, it has essentially left the building. It can be fitted with keylogging and screen-capture software to record passwords and other sensitive information. It can be used to send spam, conduct distributed denial-of-service attacks, host Web sites, and spread malware."Botnets are the most dangerous enemy that the Internet has faced up until now," Scott Chasin, CTO of anti-spam and anti-virus software maker MX Logic and chairman of the Messaging Anti-Abuse Working Group's BotNet subcommittee, recently told my colleague Larry Greenemeier.

Bots can also be used to commit click fraud. In May, Panda Software detected a click-fraud botnet that involved 34,000 computers. It likely won't be the last--I'm told there are about 70 million PCs out there that are compromised with bot software.

Google and Yahoo have both gone to great lengths to spread the world that click fraud is manageable. I wonder. In researching an upcoming story about bots, I spoke with Brett Glass, owner of Lariat.net, an ISP in Wyoming. His experience with click fraud suggests that Click Forensics' estimate that about 14% of clicks are fraudulent may be far too low. Glass told me that in a recent online ad campaign, he found only 1% of the clicks were legitimate, based on his analysis of the data.

An extreme case perhaps, but if I had a bot army at my disposal, click fraud would probably look pretty appealing. (Having seen HBO's Oz, I'm eager to avoid prison, even if most click fraudsters get away with it.)

"The search engine companies don't have any strong incentive to stop click fraud because they make money off it," Glass said.

And that's the least of the bot invasion. Larry also interviewed Marcus Sachs, a deputy director in SRI International's Computer Science Laboratory who served on the President's Critical Infrastructure Protection Board and helped in 2003 deliver the Bush Administration's National Strategy to Secure Cyberspace. Sachs explained that bots have become a "fact of life" now that up to 80% of all home PCs have been infected by some type of malicious code. "These same home users make the same mistakes at work," Sachs observed.

Enjoy the rest of Cyber Security Awareness Month, which is to say the rest of your life.