SpamCannibal blocks spam at the source by preventing the spam server from delivering the messages from its mail transfer agent (MTA) process while it is running. It tells the spam server to send very small packets. Then it causes the spam server to retry sending them over and over again, ideally bringing the spam server to a virtual halt for a long time, or indefinitely.
SpamCannibal does not identify spam. Instead, it uses a list of spam sources (IP addresses) to know what to block. SpamCannibal rejects email from entire ranges of IP addresses, including providers that host companies that are sending spam, and single IP addresses that fall within that range.
- Listings occur at the IP address and IP address ranges.
- The impact on deliverability is minimal.
- Reputable senders rarely appear on SpamCannibal.
Reasons for getting listed
IP addresses are listed for:
- Sending email to SpamCannibal mail servers, which are spam traps
- Sending email containing viruses to SpamCannibal mail servers
How to get off this blacklist
SpamCannibal has an IP lookup page, which is where you can confirm that IP addresses are listed and request removal.
Tips for staying off this list
- Conduct an infrastructure review and security check; you may have a virus sending spam to a SpamCannibal mail server
- Do not send email from a dynamic IP address
- Ensure all IP addresses have a non-generic and unique reverse DNS (PTR) record