Symantec Corporation released its July monthly State of Spam report and one of the more startling trends in the report is the growing use of PDF image spam.
Symantec noted in the report that they had ‘observed over 25 million messages that were categorized as PDF spam.’
Symantec said the PDF spam has been pushed out in two variants thus far. The first one is in a newsletter variant where a spammer makes the attachment resemble an authentic newsletter.
The second type of PDF spam the report noted comes in the form of what the company termed ‘pump and dump stock spam.’ In June this was the prevailing type of PDF spam and once opened the PDF file displays an image of a stock symbol and text encouraging a buy from readers.
In particular on the ‘pump and dump stock spam’, the company said in the past couple weeks they’ve seen German stock spam, where the spam is delivered in PDF format and instead of an obfuscated image, the PDF is formatted to more closely resemble a newsletter and specifically hypes German stocks.
As PDF usage continues its ubiquitous growth, unfortunately so does the spammers creative use of it to engage readers to buy into bogus offerings.
You can find the full report on the Semantec website.