What’s behind this mountain of spam I’m receiving?

According to a report currently whizzing around the net, 40 per cent of spam comes from just one source – which might make you wonder why a few intrepid police don’t just get in there and unplug the bloody machine. But they’d have a job doing so; the source is actually a botnet, a network of tens of thousands of machines whose security has been compromised via dodgy internet sites. This botnet makes the owners of said machines – i.e. you and I – unwitting pawns in the spam industry; indeed, our lackadaisical attitude to online security is the driving force behind it, with just six botnets are responsible for 80 per cent of all spam. You could, therefore, conceivably be in the embarrassing position of having actually sent spam to yourself.

The biggest botnet is known as Srizbi, and it’s a fairly sophisticated beast. It runs on your PC without showing any signs that it’s at work; it provides the spammer with details of any dead email addresses in its colossal list (some 162 million strong); and within the spam messages are links to sites containing more copies of the virus, thus spreading the thing further and wider. All that’s required for a torrent of spam to be unleashed is a few mouse clicks at the botnet’s HQ, and our PCs leap into action.

While Srizbi is obviously malicious in its intent, it doesn’t do any noticable harm to your computer. In fact, its invisibility on each individual machine is the key to its success; if you knew it was there, you’d obviously try and get rid of it. Protecting against it isn’t difficult, as all the main anti-virus programs have been able to detect Srizbi for some months now, but it’s nevertheless managed to establish itself on enough unprotected machines to rise to the top of the spamming heap. So by all means curse the people who wrote Srizbi, but failing to keep your anti-virus software up to date isn’t helping the situation. And nor are the men – you know who you are – who keep the industry alive by actually forking out for pills that supposedly add “bonus inches” to your “power drill”.