Spamming took a disturbing new turn when filtering firm SurfControl reported three instances of unsolicited junk mail advertising paedophile websites over the last few weeks.
Martino Corbelli, marketing manager at SurfControl, warned that such mail - known as 'paedospam' - was not only sickening, but could also land companies in trouble.
If a user inadvertently clicked on a pornographic website, content from the depraved site could then be stored on a company's web server cache; this would be a criminal offence.
"I was somewhat shocked when I received an email - which was just text, no images - which said 'click here to see naked pictures of six- to 10-year-olds'," said Corbelli.
"It was quite explicit in what it was offering, but there was no explicit material in the email itself; it was just text with a web link."
He did not click on the link but immediately forwarded the email to the FBI to investigate further. Since then Corbelli has received two other equally disturbing spam emails relating to scenes of rape.
But experts doubt that paedophiles are behind the spam.
"It is just so alien to everything we understand of how paedophiles work," said Neil Barrett, security consultant at IRM. "They are far too secretive and far too protective. The material that they have got is their 'wealth' and their trading ability with other paedophiles."
Barrett added that he could suggest only two possible reasons why this is happening, but expressed sceptism over the likelihood of either.
One theory is that the spam is the work of paedophile website administrators looking to widen their catchment area. The other is that paedophiles fearing arrest may be looking to cite such spam as an excuse for why illegal material is on their system.
But Barrett said: "I have spent a lot of time with the police helping track and catch the real paedophiles; they're not in a million years going to do this kind of thing."
When contacted by vnunet.com, the National Hi-Tech Crime Unit (NHTCU) said it was unaware of the issue but that it would alert the Internet Watch Foundation (IWF), which monitors the internet for child abuse.
"We are not actively investigating any particular information that has come to us," said a spokeswoman for the NHTCU. "But if it had a serious organised element to it, then it is something that we would look at."
A spokesman for the unit added: "If anyone receives spam promoting paedophile material they should contact the IWF, who will then act on their own authority or contact the relevant law enforcement agency."
The IWF can be contacted at www.iwf.org.uk.
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