The number of spam emails featuring shortened hyperlinks has sky rocketed over the past year, according to a new report.
On 30 April 2010 spam containing shortened hyperlinks hit a peak of 18 per cent of all spam with 23.4 billion such messages sent out, a Symantec MessageLabs Intelligence report showed.
This is twice the 9.3 per cent peak level reached on 28 July 2009.
In the second quarter of 2009, there was only one day where shortened hyperlinks appeared in more than one in 200 spam messages, but in the same period this year there were 43 such days.
There were 10 days in the second quarter of 2010 when at least five per cent of all spam contained such links.
The report also revealed the Storm botnet, making a reemergence onto the threat landscape, was responsible for the highest volume of botnet spam containing shortened hyperlinks, representing 11.8 per cent of all such messages in May 2010.
As for how many people are actually clicking through, MessageLabs Intellience discovered that on average one website visit is generated for every 74,000 spam emails with a shortened URL link.
Paul Wood, MessageLabs Intelligence senior analyst at Symantec Hosted Services, said this figure suggests spammers using shortened URL links are having "a significant degree of success".
"Some of the campaigns seem to generate more click-throughs than others. In one example, 63,000 website visits were generated from just one shortened URL. That's pretty good going, I think," Wood told IT PRO.
"Whether they used other ways of getting that [link] out than just spam they may have appeared elsewhere on the internet. They may have appeared through social networking websites, maybe even accounts that have been phished or hacked."
