Barracuda Spam Firewall Now Rejects Invalid Non-Delivery Report Messages

Barracuda Networks (News - Alert) Inc., a provider of email and Web security appliances, has announced a new feature in the Barracuda Spam Firewall that blocks bounce messages resulting from spoofing attacks. This feature can differentiate legitimate Non-Delivery Report (NDR) messages - also known as bounce messages - from invalid NDR messages resulting from spoofing attacks.

 

The Barracuda Spam Firewall prevents “backscatter” messages from reaching innocent email senders, with the help of Invalid Bounce Suppression.

 

To send spam, viruses or worms, spammers, hackers or other users with malicious intent, spoof the email addresses of legitimate email users. This is identified by Backscatter and the receiving email server typically rejects the email and sends an NDR message to the spoofed email address. The legitimate email user receives a bounce message for emails that they never sent as a result of this.

 

 

Apart from providing Invalid Bounce Suppression, the latest Barracuda Spam Firewall version also includes additional rules governing email policy. This includes new policy rules for character sets used in emails and attachments, reverse DNS resolutions for sending email servers, and full URLs (including query strings) embedded in emails.

 

The Barracuda Spam Firewall is available in eight models with prices starting at $899.

 

“Backscatter is an unfortunate side effect of the continued prevalence of email spoofing by spam campaigns that is now plaguing corporate email servers,” said Stephen Pao, vice president of product management for Barracuda Networks.

 

“It is also a frustrating, and sometimes confusing, problem for email users who are the innocent victims. While one common technique to minimize the impact of backscatter is to simply define policies to block all incoming bounce messages, doing so can result in the blocking of legitimate bounce messages. As such, distinguishing legitimate from invalid bounce messages can be extremely important to users who send business-critical email.”