/etc/exim4/conf.d/acl/40_exim4-config_check_data

### acl/40_exim4-config_check_data
#################################

# This ACL is used after the contents of a message have been received. This
# is the ACL in which you can test a message's headers or body, and in
# particular, this is where you can invoke external virus or spam scanners.

acl_check_data:

  # Deny unless the address list headers are syntactically correct.
  #
  # If you enable this, you might reject legitimate mail.
  .ifdef CHECK_DATA_VERIFY_HEADER_SYNTAX
  deny
    message = Message headers fail syntax check
    !acl = acl_whitelist_local_deny
    !verify = header_syntax
  .endif


  # require that there is a verifiable sender address in at least
  # one of the "Sender:", "Reply-To:", or "From:" header lines.
  .ifdef CHECK_DATA_VERIFY_HEADER_SENDER
  deny
    message = No verifiable sender address in message headers
    !acl = acl_whitelist_local_deny
    !verify = header_sender
  .endif


  # Deny if the message contains malware. Before enabling this check, you
  # must install a virus scanner and set the av_scanner option in the
  # main configuration.
  #
  # exim4-daemon-heavy must be used for this section to work.
  #
  # deny
  #   malware = *
  #   message = This message was detected as possible malware ($malware_name).

  # Add headers to a message if it is judged to be spam. Before enabling this,
  # you must install SpamAssassin. You also need to set the spamd_address
  # option in the main configuration.
  #
  # exim4-daemon-heavy must be used for this section to work.
  #
  # Please note that this is only suiteable as an example. There are
  # multiple issues with this configuration method. For example, if you go
  # this way, you'll give your spamassassin daemon write access to the
  # entire exim spool which might be a security issue in case of a
  # spamassassin exploit.
  #
  # See the exim docs and the exim wiki for more suitable examples.
  #
  # warn
  #   spam = Debian-exim:true
  #   message = X-Spam_score: $spam_score\n\
  #             X-Spam_score_int: $spam_score_int\n\
  #             X-Spam_bar: $spam_bar\n\
  #             X-Spam_report: $spam_report

  # This hook allows you to hook in your own ACLs without having to
  # modify this file. If you do it like we suggest, you'll end up with
  # a small performance penalty since there is an additional file being
  # accessed. This doesn't happen if you leave the macro unset.
.ifdef CHECK_DATA_LOCAL_ACL_FILE
.include CHECK_DATA_LOCAL_ACL_FILE
.endif

  # accept otherwise
accept

/etc/exim4/local_acl_data

## Reject messages containing malware.
## Reject after DATA
##
#deny message = This message contains a virus ($malware_name) and has been rejected
#demime= *
#malware = *

#
#
#
deny  message = This message contains an unwanted file extension ($found_extension)
      demime = scr:vbs:bat:lnk:pif:bz2:exe:com

# Reject messages that have serious MIME errors.
# This calls the demime condition again, but it
# will return cached results.
deny message = Serious MIME defect detected ($demime_reason)
demime = *
condition = ${if >{$demime_errorlevel}{2}{1}{0}}

#
#
#
deny  condition = ${if match{$header_subject:}{\NTestSubject\N} {yes}{no}}
        log_message = Subject Test
        message = Subject Test