Reducing Backscatter and Spam
Backscatter is a side effect of spammers sending forged bulk messages that appear to come from valid email addresses. This guide explains what backscatter is, how it happens, and how to reduce it.
What is Backscatter?
Backscatter occurs when spammers forge legitimate email addresses as the sender of their messages to bypass spam filters. When these fake messages are rejected, the bounce notifications are sent back to the innocent “sender” address rather than the spammer.
Here’s how it typically happens:
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A spammer creates a message with a forged “From” address (for example, kally@example.com).
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The spammer sends the forged message to a recipient outside the ruachost.com domain.
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The recipient’s mail server detects the message as spam and rejects it.
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The mail server sends a bounce notification to the forged sender address (kally@example.com).
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Kelly’s inbox now receives a bounce message, known as backscatter.
When spammers send large volumes of such messages, this process can generate hundreds or thousands of unwanted bounce notifications.
Reducing Backscatter
While there is no single fix that can eliminate backscatter completely due to the way SMTP works, you can reduce its likelihood with these steps:
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Limit public email exposure: Avoid posting real email addresses directly on your website. Automated bots crawl pages to collect addresses for spam. Instead, use a contact form or display your email in an obfuscated format such as kelly [at] example [dotcom]. You can also use JavaScript tools to hide addresses from bots.
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Enable Sender Policy Framework (SPF): Configure SPF records for your domain to help mail servers verify authorized senders and reduce forged emails. While not all mail servers honor SPF, it can still help reduce backscatter.
Following these practices helps minimize unwanted bounce messages and protects your domain’s email reputation.
