KEY POINTS:
Cyber criminals have used every trick in the book to sucker computer users into clicking links that will infect their machines.
But spam levels are on the up as a new outbreak has raised alarms with internet security specialist Marshal - because some people think they've been caught
on video naked.
Marshal's spam-monitoring Trace team in Auckland were the first to report the malware outbreak.
The spam emails use a personalised subject line that reads 'We caught you naked, (name here)! Check the video'.
But rather than finding a video of themselves starkers, those who take the bait and click the link just end up with an infected PC that's part of the massive Srizbi botnet.
"This is a simple but clever form of social engineering," says Marshal's VP of products Bradley Anstis.
"It is personalised by taking the name component of your email address and inserting it into the spam subject line. It is not a new trick by spammers, but it is proven to get your attention.
"In addition to this, the message seeks to embarrass you by claiming to have video footage of you naked. The spammers are clearly hoping to shock unsuspecting recipients into investigating this compromising footage.
"In their haste to look into the claim, some people might not consider the message is malware," explained Bradley Anstis, Marshal Vice-President of Products.
Marshal has identified the Srizbi botnet as the largest spamming botnet currently on the web - responsible for 45 per cent of spam caught my Marshal's Trace team.
Other researches claim Srizbi is the world's largest botnet bar none - comprising 315,000 bots and responsible for an estimated 60 billion messages per day.
"We consider Sirzbi the biggest current spam threat," Anstis warns. "In December last year, we attributed 20 per cent of the spam we caught to Sirizbi and now it is more than double that and more than double the next biggest botnet in terms of its spam volume.
"We have observed individual Sirzbi bots sending as much as 8,000 spam messages per hour,"
Marshal's researchers say the Storm botnet - which still gets a lot of mainstream media publicity - taught cyber criminals lessons in how to build an effective botnet.
"It (Storm) was certainly a major pioneer in botnet development but today it is responsible for just 1 per cent spam," he says.
"The biggest lesson that Storm taught spammers was the power of simple social engineering as a means of infecting computers and propagating a botnet. The simplest tricks are the best and this new one certainly fits the criteria."
The Trace team is currently measuring spam levels at 83.3 per cent of all email.
