Botnets are the next big danger to hit the internet according to police. Criminal gangs are moving into the field in order to use the networks to extort money from online companies.
Speaking at the Secure London 2005 event on Thursday, Detective Sergeant Steve Santorelli of the Metropolitan Police Computer Crime Unit said the police were making headway in the battle against botnets.
"Law enforcement is putting a large amount of effort into identifying people behind the botnets and dismantling their networks," he said.
Botnets used to be the work of bored teenagers using networks of infected computers to gain points on online games such as Outwar. These networks are controlled through channels on IRC. The controller or "Botnet Pimp" then gives a command to the infected computers to launch an attack on a website or send spam. Usually, these pimps try to infect "high-quality" computers where bandwidth is high, such as academic, corporate or government machines.
However, police has been investigating a number of cases where botnets are being used to take down gambling websites. Gangs launch a Distributed Denial of Service (DDoS) attack for half an hour then send an email to the website's administrator demanding large sums of money to stop a repeat attack.
Despite this worrying trend Santorelli said the police have "had a number of significant successes, many of which we expect to see at court over the coming months."
He advised corporate users to review logs at regular intervals and have IDS systems in place to monitor traffic for unauthorized SMTP traffic which may suggest a spammer's proxy within the network and to look out for traffic on ports that should not be there.