Postfix block PDF or ZIP files attachments

Q. How do I block all PDF or ZIP files attachments under Postfix Mail Server?

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A. You can easily block email attachments using mime header check.

Open postfix config file

Login as the root, enter:
# vi /etc/postfix/main.cf

Block zip or pdf files

Use mime_header_checks postfix config directive, enter:
mime_header_checks = regexp:/etc/ostfix/block_attachments
Save and close the file. Open /etc/ostfix/block_attachments file and append code as follows:
/name=[^>]*\.(pdf|zip)/ REJECT
Save and close the file.

Restart Postfix MTA

You must restart or reload postfix:
# /etc/init.d/postfix reload

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4 comments… add one
  • Mustafa Sep 20, 2011 @ 14:08

    Hi,
    This will block attachments for all the accounts on the server, what I want to do is block all outgoing attachments for one account.
    Is there is a way to do that ?

  • Itelica Apr 26, 2013 @ 8:19

    This worked for us, thanks. Just one thing, you have missed out the P in postfix in the regexp line entry. We noticed it and changed it but others may not.

  • Ramesh Jul 23, 2014 @ 17:08

    Hi,

    Please advice me how to block zip file include exe in postfix.

    Thanks for advance
    Ramesh

  • dxman Aug 15, 2014 @ 12:32

    hi admin,
    i am not getting bounce back email if the user tried to send email with the ( exceeded quota )attachment. mail deliver to recipient but the attachment is drop by server (if attach using the outlook)

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