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Commtouch survey show majority of service providers blacklisted in last year

Commtouch (NASDAQ: CTCH) said it has published results of a poll among recent Don´t Risk the Blacklist Stop Outbound Spam webinar participants.

The December 4 poll of the Commtouch webinar attendees shows that nearly 90 percent of their respective organizations have had an IP address appear on a blacklist in the last 12 months. The most common reason for blacklisting remains outbound spam, with the most popular outbound spam sources being:

Zombies, which are responsible for sending approximately 85 percent of all unwanted email messages, send spam directly to the Internet using port 25;

User accounts or domains created exclusively for spamming;

Cybercriminals using compromised user accounts to send out spam.

Spam is easily traced to the sending IP range, resulting in the addition of this range to Realtime Blackhole Lists. Most service providers use these blocklists to enforce message blocking rules and as a consequence, legitimate email sent from these ranges gets blocked.

“Traditional approaches, such as blocking port 25, reversed inbound spam filters, or throttling, have limitations and are ineffective in the end because they treat symptoms, but not the underlying problem,” said Lior Kohavi, chief technology officer at Commtouch. “Therefore, it is important to protect mail systems with a specialized outbound anti-spam solution that also pinpoints the spamming source. As the common characteristic of all spam is mass distribution, such a solution must be able to detect local and global recurrent patterns.”

Commtouch is a provider of Internet security technology and cloud-based services for vendors and service providers, increasing the value and profitability of our customers´ solutions by protectingbns of Internet transactions on a daily basis. To learn more, visit


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