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429 points pabs3 | 1 comments | | HN request time: 0s | source
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jeroenhd ◴[] No.43469827[source]
For me, as someone with their own mail server, these technologies mostly serve to inform me that Russian IP addresses are still trying to send email in the name of my domain for some stupid reason.

It makes sense that people whose business is sending email know how to set up email correctly. I'm mostly surprised at how many legitimate sysadmins struggle with getting the basics correct. Surely those dozens of DMARC emails you get that your sendgrid email has been refused because of a bad SPF signature should set in motion some kind of plan to ask if maybe marketing is using them legitimately?

Automated signatures are of limited value but I rarely see rejections based on SPF and DKIM that are a mistake. Things are probably worse for big organizations but as a small email server, technical rejections are usually the right call. The only exception is mailing lists, but the dozens of people who still use those can usually figure out how to add an exception for them.

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JumpCrisscross ◴[] No.43470668[source]
> Russian IP addresses are still trying to send email in the name of my domain for some stupid reason

For what it's worth, I've started seeing cybersecurity insurers requiring riders and extra payments if you don't block Russian IPs.

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1. snowwrestler ◴[] No.43477981[source]
Ok but you can’t block someone else using their own IPs to send email.

If you set DMARC to report, you’ll get notices from remote email systems when they receive noncompliant emails with your domain in the Envelope From field. Those reports are where you’ll see Russian IP addresses show up when they are trying to spoof your emails.

But there is no way to block them because neither the senders nor receivers are on your infrastructure. The best you can do is set a reject DMARC policy and hope everyone follows it.