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I like @Law29's response and will likely choose it as the best answer for this question. That being said, in case someone else stumbles across this post, here's the authoritative answer from the bat book: SIGTERM Cleanup and exit sendmail signal. Whenever sendmail gets a SIGTERM signal (as would be the case if the system were being shut ...


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Sendmail and all other properly written MTAs are written so that there are are only two possibilities: the message is first written to disk and then acknowledged to the sending MTA the message is not acknowledged With this method, there are three outcomes in case an error occurs: The error occurs before the receiving sendmail has tried to acknowledge ...


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https://support.google.com/a/answer/3726730?hl=en 450, "4.2.1" The user you are trying to contact is receiving mail too quickly. Please resend your message at a later time. If the user is able to receive mail at that time, your message will be delivered. For more information, review this article. 450, "4.2.1", The user you are trying to contact is ...


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You can use uuencode to encode the attachment. Most email clients recognize uuencoded attachments. Make sure there is an empty line after email headers in email.txt file. Sendmail expects "raw" message. #!/bin/sh (cat email.txt; uuencode foo.pdf foo.pdf)|/usr/sbin/sendmail -i -- johndow@example.com


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You really shouldn't call sendmail directly but use mail or mailx which will also help you set up the correct headers and such. Moderns version of those support adding attachments with the -a option. The alternative, is to MIME (base645) encode your attachment and include it, with the correct headers in the body of your raw email text and submit that to ...


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That's not how sendmail works. It just deals with transporting the mail and expects a properly encoded mail already. You could do this encoding yourself or just use mail/mailx/mutt instead to hand over a suitable mail over to sendmail for delivery.


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The question you might want to ask yourself, is what is the benefit in knowing what script sent the email? Certainly you should be looking to fix your security, but the exploit is not the same thing as the vulnerability - there are multiple things an attacker might do with your system, not just sending email. So really your focus should be on fixing the ...


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Did you check web log? Try to look process with ps to identify process which sending spam. Maybe you can catch it there. Second, maybe spammer periodically send by crontab, check every crontab in your system to identified the bogus script. –°heck one of the email with postcat to see which script tries to send them: postcat /var/spool/postfix/deferred/1/{$...


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I know this question is two months old, but it is a top Google search result for the subject so I figured it deserved an answer. I don't know what your second and third TXT entries are for. I have DKIM working properly now and I only have a TXT entry similar to your first one. I followed instructions from Digital Ocean when setting up DKIM on Ubuntu, but ...


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I think the issue is because mx record is not configured from virtual server. Need to make sure the following thing is done. 1) Webmin -> Servers -> Postfix Mail Server -> General Options -> What domain to use in outbound mail (Use hostname) 2) Webmin -> Servers -> Postfix Mail Server -> General Options -> What domains to receive mail for (Local machine) ...


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The mail was actually accepted on the gmail side. That is shown in the last line in which you receive the following back from the receiving server: OK 1464983764 l40si4464056qtc.52 - gsmtp The verify=fail is in regards to the TLS negotiation (I believe failing on the client side cert verification which is not typically enforced). My first thought is that ...


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Note that it's 250 8BITMIME and not 250-8BITMIME (with the dash). Would this be enough for sendmail to consider that the remote source doesn't support 8bitmime? No. This is called continuation and it only signifies that the line is the last line of the SMTP reply. And generally 8BITMIME should be the only thing required to show that the MTA on the ...


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You can modify flags of mailers provided by mc files of sendmail.org using MODIFY_MAILER_FLAGS in sendmail.mc file define your own mailer "from scratch" using MAILER_DEFINITIONS in sendmail.mc "clone & modify" mailer/*.m4 files provided in sendmail distribution


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Sendmail had used to be installed as set root uid program. Sendmail-8.12+ is no longer (by default) installed as set root uid program to avoid security risk. Sendmail executed by non root user passes messages to sendmail daemon running with root privileges at 127.0.0.1:25. Sendmail executed by non root user uses /etc/mail/submit.cf instead of /etc/mail/...



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