Spammers switching on to YouTube?

Email security company MessageLabs has warned that spammers are already modifying their tactics when it comes to the emerging trend of using audio rather than text attachments in unsolicited mail.

MessageLabs has claimed that following the first spam campaign involving audio files earlier this month, which attempted to control the value of stock for "nefarious reasons", spammers are now moving on from simply attaching audio to mail to linking through to content hosted on multimedia sites such as YouTube.

MessageLabs said in a statement: "This recent trend proves that spamming techniques are becoming more innovative. As image spam shifts from email attachments to images on free image-hosting sites, [we] believe that it is only a matter of time before the spammers apply the same approach to audio spam and upload the message to free multimedia-hosting sites, such as YouTube, Google Video, [and] MySpace."

On 17 October spammers used attached MP3 music files to try to "sneak messages past spam filters", said MessageLabs. The spam run of 15 million emails lasted 36 hours and used Storm Worm-infected computers for the purposes of dissemination, MessageLabs said.

According to MessageLabs, spammers have recently been experimenting with different types of file attachments, including text, image, HTML, ZIP, RAR, RTF and PDF file formats.

Mark Sunner, chief security analyst for MessageLabs, said: "The MP3 spam tactic is a natural progression for cyber criminals following runs of image, PDF and Excel junk mail earlier this year. As users become wary of certain file attachments, scammers will move on to their next tactic."

Sunner also predicted video spam and PowerPoint presentations would become "the next format du jour".

Earlier this month, Sophos reported that spammers were exploiting YouTube's "invite your friends" function to send email spam containing a variant of the Storm Worm.

Tom Espiner writes for ZDNet UK