Barracuda Networks, Inc. announced the availability of its third generation of image spam defense enhancements to the Barracuda Spam Firewall. This release provides even greater protection against the evolving complexity of image spam, rendering these new forms of spam ineffective. The new email security techniques dive deeper into image spam messages and automate spam fingerprint analysis to further the effectiveness of image spam filtering that protects more than 40,000 Barracuda Networks customers worldwide.
Image spam generally embeds text inside of images with the intent of hiding content from the text rules processing layers of spam filters. To combat these forms of image spam, the Barracuda Spam Firewall has been shipping an optical character recognition (OCR) engine since July 2006.
In early attempts to foil OCR engines, senders of image spam attempted to use animated GIF files to spread content across multiple frames. In addition, they attempted to obfuscate text inside their images by corrupting the images with lines, speckles and other image artifacts. To neutralize these techniques, Barracuda Networks second-generation OCR engines incorporated both animated GIF analysis and fuzzy logic to stifle text obfuscation techniques.
With the third generation of image spam defense, Barracuda Networks has incorporated a new multi-pass OCR engine. This new multi-pass engine performs deeper analysis by performing image pre-processing operations to normalize the images prior to final optical character recognition passes. This additional processing is particularly effective against attempts to hide text by varying color and contrast combinations of text and backgrounds. With these new techniques, Barracuda Networks has maintained a 95 percent accuracy rate in identifying and blocking image spam.
In addition to adding processing capabilities inside the Barracuda Spam Firewall, Barracuda Networks has also significantly enhanced the image spam defense capabilities in its backend systems at Barracuda Central, an advanced technology operations center where engineers continually monitor the Internet for trends in spam and virus attacks, and develop strategies to mitigate those threats.