Privacy Digest

Now PDF Is The Format For Spam Delivery: "The never-ending game of whack-a-spammer-mole continues, with spammers now adopting PDF files as the new mechanism for delivering their junk mail.

It seems like only yesterday we were talking about image-based spam, where the junk mail message was written in a GIF or JPEG file embedded in the letter. Now the junk mailers have been forced to change because spam blockers and detection mechanisms had gotten quite good at detecting image-based spam.

As spam filters have improved, image-based spam has taken a hit. Secure Computing notes that image-based spam has dropped from the 30 percent range to just 10 percent of total e-mail volume in recent months.

What's taking its place is a bigger nuisance. Spam in the form of attached PDF files has grown from just one percent in June to five or six percent of e-mail volume in just a month.

So it would seem PDF has replaced the GIF, according to Dmitri Alperovitch, principal research scientist at Secure Computing's TrustedSource Labs. 'The makers of e-mail filters have figured out how to recognize image-based spam and have updated their products to stop it. So now [spammers] wrap it up in the PDF,' he told internetnews.com."

(Read Original Article - Via internetnews .)