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 (hear-me.social)
submitted 2 days ago by Jerry@hear-me.social to c/cybersecurity@fedia.io
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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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[–] Jerry@feddit.online 1 points 1 day ago (1 children)

DMARC reports are sent by the receiving server, which is not the server sending the bounces. They are reports sent to the domain owner. SPF, DKIM and DMARC are only meant as tools to protect the domain owner and indicate when an email should not be accepted.

These bounces are coming from the sending server whose email attempt got rejected by the receiving server. They are NDRs which are not covered by SPF, DKIM, or DMARC.

The sending server is informing the FROM: address, as a courtesy, that the email could not be delivered, even when the sending server knows the FROM is likely fraudulent. This has nothing to do with SPF, DMARC or DKIM and is a different protocol.

Argue with Google, not me: 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