Nearly 90 pc of service providers have had IPs blacklisted in last 12 months

MCLEAN, USA: Commtouch published results of a poll among recent Don't Risk the Blacklist - Stop Outbound Spam webinar participants. The December 4th 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 (RBLs or IP blocklists). Most service providers use these blocklists to enforce message blocking rules - and as a consequence, legitimate email sent from these ranges gets blocked.

Being blacklisted often has a significant business impact, including:

* Removing the addresses from blocklists takes time and resources.

* Legitimate email senders drain support staff time with complaints.

* In a worst case scenario, customer churn is caused by the reputational damage.