Spammers *were* attaching images with spam. The tools used are actually sophisticated, such that, the placement of a pixel here and there are altered thwarting tools that perform image analysis (or a simple hash of the image) to determine if the email is spam.

Looks like the good old days are over! Move over image spam, here come the pdf spam!

I was surprised this afternoon to see an spam email in my inbox attached with a PDF! A regular spam image was the content of the PDF. Yes, I have been a good netizen and reported the email to Microsoft for further analysis.

Actually, it is no wonder to see this happening. I would think we might see some small mp3 attached spam, video attached spam or for that matter any other service by passing spam. I don’t think the solution to spam is to analyze the spam. It is to characterize the sender based on the past behavior would help. I believe that my present research in the field of sender reputation systems could help.