This post is made on behalf of my colleague Nicholas Johnston
On 27 October, MessageLabs Intelligence began tracking a small number of spam emails that included links to the popular online file transfer service, YouSendIt.com. In the latest examples, the files that were being distributed were word-processing documents that contained advanced-fee fraud lottery scams. MessageLabs Intelligence will continue to monitor this activity. YouSendIt and other similar file transfer services are used legitimately by may users to send large files via the Internet where it may not be appropriate or possible to send as an email attachment, for example if the file is too large.
This is another example of the bad guys turning to online services in order to exploit the use of their reputable services and bypass traditional anti-spam countermeasures that consider the reputation of domain names contained in hyperlinks used in email messages in order to determine the likelihood of the message being spam.