1 Topic by Pakoul

  • Pakoul
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Topic: Is iRedmail setting by default an open relay

==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): iRedMail-1.3.2
- Deployed with iRedMail Easy or the downloadable installer? Downloadable installer
- Linux/BSD distribution name and version: Ubuntu Server 20.04
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):  MariaDB
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? No
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

Hello all,

I'm wondering if postfix default setting allow servers open relay.
We're being abused every time we open our port 25.  No user yet configured on our database so it must not be weaker password context.

----

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2 Reply by Fastidious

  • Fastidious
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Re: Is iRedmail setting by default an open relay

Postfix allows anything you configured it to be, but iRedMail doesn’t setup Postfix to be an open relay.

What kind of abuse are you referring to?

3 Reply by Pakoul

  • Pakoul
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Re: Is iRedmail setting by default an open relay

Fastidious wrote:

Postfix allows anything you configured it to be, but iRedMail doesn’t setup Postfix to be an open relay.

What kind of abuse are you referring to?

~10000 mails queued in one night. Our provider had to block port 25 because it's too much.
And this is a default iRedMail installation, I didn't change anything on the configuration  files yet.

Some relevant log
https://pastebin.com/RKQLPiz1
https://pastebin.com/p06YtNxG
https://pastebin.com/2g0CbpzT

4 Reply by Fastidious

  • Fastidious
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Re: Is iRedmail setting by default an open relay

And you installed iRedMail on a brand new (and in fresh, untouched), vanilla Ubuntu machine? Your logs are hard to read, but it looks like the emails are coming from the machine itself.

A mail server can be a tricky thing. It is best to dedicate a VM for it, and nothing else. Are you doing that?

5 Reply by Pakoul

  • Pakoul
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Re: Is iRedmail setting by default an open relay

After investigations and some cold nights, looks like postfix inside container (LXC) is the source of the problem.
I installed iRedMail inside LXC then redirect to it the ports needed to open.

I now use a dedicated VM and no more open relay.