The battle between spammers and security companies gets tighter as spammers found new ways to outmaneuver measures meant to stop them.

McAfee discovered the latest trends in spam for the month of August. Two of the many statistics McAfee anti-spam researchers monitor are the duration of spam campaigns and the number of unique URL addresses used by spammers in campaigns over a given period.

Current trend data indicates that the major spam campaigns are, on average, cycling through 72 percent more domains per hour than just one month ago.

Spam messages usually contain URLs that link to Web sites where users can purchase items ranging from discounted products and medicines to other services. Spammers tend to use multiple URLs in their campaigns as way of surpassing anti-spam defenses, however they have recently stepped up their activity, using many more URLs than usual and cycling through them faster as well.

“It’s a cat and mouse game where spammers try to change their URLs faster than the anti-spam companies can react,” said Guy Roberts, development manager at McAfee, Inc. “If it takes traditional blacklists fifteen to twenty minutes to block a site, then that’s how fast the spammers need to change their URLs. Since domains cost only $6 per registration, the spammer is spending less than $100 for four hours of advertising.”

To stay ahead of this pace, McAfee utilizes streaming update technology in its anti-spam products to keep them up-to-date and to maintain a high block- rate. McAfee’s unique implementation of domain name reputation technology can predict malicious and/or spammer Web sites even before the sites have been involved in a spam campaign, which helps to block “day zero” spam.