PDF Spam Surges Profusely in Fourteen Days

Whenever it seems that spam is going down, there comes news that breaks our myth. During the weeks August 2, 2007 to August 16, 2007, PDF spam jumped nearly 500% from a low of 5% of total spam to almost 25% of the entire spam that Proofpoint Attack Response Center observed. On the other hand, image spam using Joint Photographic Experts Group (JPEG) or Graphics Interchange Format (GIF) has accounted for less than 4% of the entire spam during the reported period.

Spammers have come to find that a majority of the different anti-spam solutions are not designed to assess PDF attachments, so they conveniently insert whatever spam content they have, whether in images or text, in the PDF files, said Andres Kohn, vice president of product management for Proofpoint Inc. Dark Reading published Kohn's statement on August 17, 2007.

As per observations by Proofpoint, there were less numbers of PDF spam many months back, but their volumes exceeded even image spam in early August 2007 and during August 2-16, 2007, the volume quintupled, Kohn added.

Talking on similar lines, David Salbego, Unix and operations manager of computing and information systems with Argonne National Laboratory, said the growth of image spam that has now peaked simply represents another new growth in the scenario of the constantly evolving spamming techniques. While some PDF spam has emerged, there are more to come. This is just another tool in the typical spammer's arsenal, said Salbego. PC World reported this on August 16, 2007.

Salbego went on to say that eventually filtering of spam content would increasingly become less effective. Salbego thinks a more effective way to deal with spam would be to determine the message source i.e., the IP address of the server from where the e-mail originates.

Kohn concluded by saying that new types of spam are getting more sophisticated while there is a consistent rise in spam levels with the messages targeting enterprises. Therefore, organizations need a technology that would address both the new, complex attacks and discard as many 'spammy e-mail connections' as are feasible.

Related article: PDF flaw gets fixed with Adobe patch

» SPAMfighter News - 9/5/2007