diff --git a/roles/mail/templates/postfix/main.cf.j2 b/roles/mail/templates/postfix/main.cf.j2
index 815b3ba..eb3e95d 100644
--- a/roles/mail/templates/postfix/main.cf.j2
+++ b/roles/mail/templates/postfix/main.cf.j2
@@ -99,6 +99,9 @@ smtpd_recipient_restrictions =
     reject_unauth_pipelining
     reject_unverified_recipient
 
+# SMTP Smuggling
+smtpd_forbid_bare_newline = yes
+
 # rspamd Milter setup
 smtpd_milters = inet:localhost:11332
 non_smtpd_milters = inet:localhost:11332