this post was submitted on 26 Apr 2025
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Did you know that if a spammer uses your email address as the FROM: address, which is easy to do, all the bounce messages will go to your email address? If the spammer really hates you, they will send millions of emails with your FROM: address and you will get a million bounce messages.

Can you stop this or prevent this? No

Why would a mail provider send you a bounce message, knowing you're innocent? Because that's how someone wrote the protocol back then, and nobody changes it or does it differently because ... reasons.

Does the spammer get a bounce message? Nope, not one.

Does the SMTP sending account owner whose credentials were stolen be notified about bounces so they can stop the spam? Nope.

Just millions of emails sent every day to poor schlameels who have no idea why they are getting them and who can't do anything about them.

The more I learn about the email protocols, the more I realize how terrible the design is.

#emailsecurity #spoofing #cybersecurity #spam

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[โ€“] renormalizer@feddit.org 2 points 1 day ago (1 children)

I'm very sure that, by default, at least postfix will send bounces only to local senders. So unless the spammers use your SMTP server to send spam, you shouldn't get any bounces. If they do, you have different problems.

[โ€“] Jerry@feddit.online 1 points 1 day ago

Tell that to hotmail because they keep sending it. And be sure to update Google too because they don't know as much as you either. https://support.google.com/mail/thread/209018675/my-sent-email-box-is-filling-up-with-bounce-emails-and-emails-i-did-not-send-my-inbox-is-fine?hl=en