exim -bV

Support for: ... Content_Scanning ...

apt install spamassassin

cd /etc/spamassassin/
cp local.cf local.cf.old

mcedit local.cf

required_score  5.0
report_safe     1
use_learner     1
use_bayes       1
bayes_auto_learn  1
bayes_path      /etc/spamassassin/bayes_dir/bayes
bayes_file_mode 0666
bayes_min_ham_num  200
bayes_min_spam_num  200
bayes_learn_to_journal 0
skip_rbl_checks 1

mkdir /etc/spamassassin/bayes_dir

Проверяем все ли установлено

spamassassin --lint

sa-learn --sync
chown -R Debian-exim /etc/spamassassin/bayes_dir/
chmod 666 /etc/spamassassin/bayes_dir/*
systemctl start spamassassin.service
systemctl enable spamassassin.service

mcedit /etc/exim4/exim4.conf

#MAIN CONFIGURATION SETTINGS
...
acl_smtp_data = acl_check_content
...
#Необязательно указывать если это локальный хост.
#Если spamd будет недоступен, в результате будет временная ошибка,
#если есть настройки acl_check_content
#spamd_address = 127.0.0.1 783
...
#ACL CONFIGURATION
begin acl
acl_check_rcpt:
...
acl_check_content:
  accept hosts = 192.168.150.0/24 : 192.168.151.0/24
  accept condition = ${if > {$message_size}{5M}}

# put headers in all messages (no matter if spam or not)
  warn  spam = nobody:true
      add_header = X-Spam-Score: $spam_score ($spam_bar)
      add_header = X-Spam-Report: $spam_report
# add second subject line with *SPAM* marker when message
# is over threshold
  warn  spam = nobody
      add_header = Subject: *SPAM* $h_Subject:
# reject spam at high scores (> 12)
  deny  message = This message scored $spam_score spam points.
      spam = nobody:true
      condition = ${if >{$spam_score_int}{120}{1}{0}}
accept

systemctl restart exim4