efa-project.org

you are free to do what you wish with your own mailserver.

Maybe I didn't state it correctly as my knowledge is not perfect.

Ports 25, 465 and 587 are all use for SMTP transmission which may or may not be encrypted. The rest is just details.

Modern mail servers prefer encrypted connections. Old mail servers are happy to use unencrypted.

Many ISPs block ...

1/ create the account X
2/ add the account X to the wheel group in /etc/groups. Your first admin account (FAA) will already be there. Separate the account names with a comma
3/ cp /home/FAA/.bashrc /home/X/
4/ chown X.X /home/X/.bashrc
5/ log into account X and see if it's working

That's it.

Do ...

Here's a good and current working configuration for EFA v4 postfix-sasl by ajmind

viewtopic.php?p=19136#p19136

Helpful!

Thats answering me, that you open port 587 to the outside and somebody brute force trying to make your EFA Box as SMTP Relay and your secure log is generating error report. Or you open port 587 cause you use authentication level on your mailserver to communicate to your EFA Box for outbound ...

I'm thinking like conventional mail server, Postfix SMTP server uses Dovecot SASL, and this Dovecot SASL Authentication to authenticate/validate POP/IMAP clients.

It's also to authenticate encrypted smtp connections. No pop/imap required.

CMIIW is that because the op open port dovecot to the ...

In my eFa.local jail:
[snip]

Thank you, that is very helpful. I previously knew nothing about fail2ban, so I previously did some voodoo and got it working well enough.

Now that I actually want to do something specific, I've had to spend the last couple of days reading up on the software, how it ...

<sender@fake-domain.com>: Sender address rejected: Access denied; from=<sender@fake-domain.com> to=<our-client@own-fake-domain.com>

This is your problem. EFA/postfix is rejecting the message because it does not like the sender address for some reason.

Can you check your /etc/postfix/main.cf ...

postfix doesn't do sasl authentication. Instead, it hands it off to another program: http://www.postfix.org/SASL_README.html#server_sasl_enable

If you look in your /etc/postfix/master.cf, you will see that the submission process has the following parameters (or it does on mine):
submission inet n ...

What changes did you make to your postfix-sasl jail configuration?

I was looking through the configuration and I noticed that there is a way to integrated it with blocklist.de, a fail2ban reporting site. The idea is, if multiple people are reporting the same ips, then everyone can get the benefit ...

my server only allows the three smtp ports open

the authentication attempts are happening over smtp.

dovecot is just acting as the authenticator.

Ask yourself where are the login attempts coming from and what program are they trying to connect to?

Answer: dovecot.

dovecot is the imap and pop server process that manages mailboxes for external users. It also provides user authentication for smtp connections.

So have a look at your /var/log ...

Without the original message to examine, I don't have a solution other than to disable the "No executables" rule inside of MailScanner in the filetype rules configuration files.

Oh, hey, look! I found this in the EFA slack channel

Ben
2:58 PM
Hey, is there any to fix the MailScanner: No programs allowed (220000.dat) and allow .dat files?

Shawn Iverson
6:53 PM
In /etc/MailScanner/MailScanner.conf:
Archives: Ignore DAT File Executable = yes

What are your settings ...

Ok, so that is weird.

I cannot reproduce the problem.

Is it possible for you to forward me an email as an attachment that is triggered by your efa system? I would like to inspect the email in question to see if I can work out why it is trigguring the "No executables" rule.

Maybe there is an ...

You're welcome. It's actually a question I had for myself, but I was previously too lazy to get off my ass and work it out.

If all goes well and they do implement it, I will aks if we can mentione their name as users.
I belive this would be great advertising.
Paraticularly because they have centralised relays for all their email globally.


Banks are touchy about exposing information. Don't worry about it too much.

On ...

a compromised dkim key are not the end of the world because it is only 1 part of the entire verification/authentication process. There is still the SPF record, the dmarc settings for verifying whether the message is legitimate or not.

Just the same, change the keys occassionally. Office365 creates ...

My first reaction would be to say "create a separate dkim record for each signing mta".

Each dns txt record would need to be unique to each mta.
e.g.
efa1: KeyTable
mta1._domainkey.example.com...

efa2: KeyTable
nta2._domainkey.example.com...

However if both machines are serving mail for all ...

I'm also testing with the EICAR test virus (https://www.eicar.org/download-anti-malware-testfile/) and that gets blocked properly.

[edit: ignore the following. MS_FOUND_SPAMVIRUS is one of my own custom rules.]

Comparing the two messages, I am seeing the following

the spamassassin MS_FOUND ...

followup here:
viewtopic.php?p=19108&sid=3c96a92effbda ... d60#p19108

Similarly, from this thread
https://forum.efa-project.org/viewtopic.php?p=19107#p19107

clamav is passing on a file it thinks is a virus:
Aug 9 16:43:19 efa4 MailScanner[25395]: New Batch: Scanning 1 messages, 76484 bytes
Aug 9 16:43:19 efa4 MailScanner[25395]: Virus and Content Scanning: Starting ...

I got it.

clamav definitely detects is, and then it gets delivered.

investigating.

for "ReportAddress" in /etc/opendkim.conf, only use 1 email address.

your /etc/opendkim/KeyTable is correct.

your /etc/opendkim/SigningTable is correct.

your /etc/opendkim/TrustedHosts looks correct.

My own multidomain configuration matches yours and it works for me.

Did you test your dkim ...

ok, the white list is SQL Grey in operation and it is working as designed.

SQL Grey is a way of blocking spam from "fake" mailservers. If a message from a new sender is rejected with the temporary error, most of the fake sending mail servers will not resend and that spam will be never enter the ...