Barracuda Networks announced it has seen a more than 67 percent increase in overall spam volume and a 500 percent increase in image spam since August. This increase is attributed to a number of trends, including a significant uptake in the number of penny stock promotions that Barracuda Central, an advanced technology operations center where engineers continuously monitor the Internet for trends in spam and virus attacks, has seen hitting the millions of inboxes of its more than 35,000 customers worldwide.
Simple-text messages can be difficult to detect and block because they are created to look like a legitimate text email. The volume of text spam has particularly increased with the popularity of stock spam because these forms of spam are particularly well-suited for text-only email. The call to action is simply to transact a stock; therefore these emails need not reveal their intent through embedded URLs or HTML tags.
Stopping text-only spam generally requires a rapid tactical response. Obfuscating text spam usually involves misspelling key words or randomly inserting unrelated phrases to throw off spam filters. Sophisticated spammers generally design and test their messages against the current spam definitions of popular spam filters. Therefore, blocking these spam messages engineered to pass through filters requires both early detection of an outbreak and rapid deployment of mitigation strategies.
In addition, Barracuda Networks reports a considerable climb in the volume of image-based spam, a trend that began more than six months ago and which the Barracuda Spam Firewall includes strong measures of protection against. Because developing stock spam that can pass through popular spam filters often requires the spammer to degrade the readability of the messages, stock spam also makes up a significant percentage of image spam. Using OCR (Optical Character Recognition) techniques, and unique fingerprint methods, the Barracuda Spam Firewall has an effectiveness rating of more than 93 percent against image-based spam.