Its simple.
Insert a rule, which disallows messages that are originating from your
domain but aren't authorized to relay.
This check can be done both on MAIL FROM and Mime From level.
Something like this in acl_mail:
accept
authenticated = *
sender_domains = nk.ca
set acl_m0 = authorizedrelay
deny
message = You can't spoof the domains this server is authorative for
sender_domains = nk.ca
then in acl_data:
deny
message = You can't spoof the MIME From this server is authorative for
condition = ${if match {$h_from:}{^(?i).*<.*@(.*\\.nk.ca>\$}{yes}{no}}
condition = ${if eq {$acl_m0}{authorizedrelay}{no}{yes}}
That will block these form of spam that spoof your sender.
Den sön 27 jan. 2019 kl 13:44 skrev The Doctor via Exim-users
<exim-users@???>:
>
> I am certain many of you have seen this, but how do you block / bounce said
> below e-mail via exim using spamassassin / clamd ?
>
> Using FreeBSD 11.2 ports of Exim.
>
>
>
> ----- Forwarded message from doctor@??? -----
>
> Date: 27 Jan 2019 07:21:14 -0300
> From: doctor@???
> To: doctor@???
> Subject: Your account has been hacked! You need to unlock.
> Subject: {SPAM?} Your account has been hacked! You need to unlock.
> X-Mailer: Microsoft Outlook 14.0
>
> Hello!
>
> I have very bad news for you.
> 12/10/2018 - on this day I hacked your OS and got full access to your account doctor@???
>
> So, you can change the password, yes... But my malware intercepts it every time.
>
> How I made it:
> In the software of the router, through which you went online, was a vulnerability.
> I just hacked this router and placed my malicious code on it.
> When you went online, my trojan was installed on the OS of your device.
>
> After that, I made a full dump of your disk (I have all your address book, history of viewing sites, all files, phone numbers and addresses of all your contacts).
>
> A month ago, I wanted to lock your device and ask for a not big amount of btc to unlock.
> But I looked at the sites that you regularly visit, and I was shocked by what I saw!!!
> I'm talk you about sites for adults.
>
> I want to say - you are a BIG pervert. Your fantasy is shifted far away from the normal course!
>
> And I got an idea....
> I made a screenshot of the adult sites where you have fun (do you understand what it is about, huh?).
> After that, I made a screenshot of your joys (using the camera of your device) and glued them together.
> Turned out amazing! You are so spectacular!
>
> I'm know that you would not like to show these screenshots to your friends, relatives or colleagues.
> I think $639 is a very, very small amount for my silence.
> Besides, I have been spying on you for so long, having spent a lot of time!
>
> Pay ONLY in Bitcoins!
> My BTC wallet: 145SmyE7DBEQExsnXZobojbQqr5UdgbCHh
>
> You do not know how to use bitcoins?
> Enter a query in any search engine: "how to replenish btc wallet".
> It's extremely easy
>
> For this payment I give you two days (48 hours).
> As soon as this letter is opened, the timer will work.
>
> After payment, my virus and dirty screenshots with your enjoys will be self-destruct automatically.
> If I do not receive from you the specified amount, then your device will be locked, and all your contacts will receive a screenshots with your "enjoys".
>
> I hope you understand your situation.
> - Do not try to find and destroy my virus! (All your data, files and screenshots is already uploaded to a remote server)
> - Do not try to contact me (this is not feasible, I sent you an email from your account)
> - Various security services will not help you; formatting a disk or destroying a device will not help, since your data is already on a remote server.
>
> P.S. You are not my single victim. so, I guarantee you that I will not disturb you again after payment!
> This is the word of honor hacker
>
> I also ask you to regularly update your antiviruses in the future. This way you will no longer fall into a similar situation.
>
> Do not hold evil! I just do my job.
> Have a nice day!
>
>
> ----- End forwarded message -----
>
> --
> Member - Liberal International This is doctor@@nl2k.ab.ca Ici doctor@@nl2k.ab.ca
> Yahweh, Queen & country!Never Satan President Republic!Beware AntiChrist rising!
> https://www.empire.kred/ROOTNK?t=94a1f39b Look at Psalms 14 and 53 on Atheism
> Birthdate: 29 Jan 1969 Redhill, Surrey, England, UK
>
> --
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