A method to cut down computer's spam diet

London: A group of computer scientists have come up with a method that deciphers the templates a botnet uses to create spam, and these templates are then used to teach spam filters what to look for. This can be used to block the most common kind of spam.

Most spam messages originate in networks of compromised computers, called botnets, and owners are unaware that the machines quietly run malicious software in the background that pump out spam, reports New Scientist. But researchers have now come up with a system that deciphers the templates a botnet is using to create spam, and these templates are then used to teach spam filters what to look for.

The system, developed by a team at the International Computer Science Institute in Berkeley, California, and the University of California, San Diego, works by exploiting a trick that spammers use to defeat email filters. As spam is churned out, subtle changes are typically incorporated into the messages to confound spam filters.

To test their idea, the team installed a previously captured software bot onto a machine. After analysing 1000 emails generated by this compromised machine - less than 10 minutes' work for most bots - the researchers were able to reverse-engineer the template.