On Thu, Jul 07, 2022 at 01:01:22PM -0400, Bill Cole wrote: > > mua_recipient_restrictions = permit_mynetworks > > permit_sasl_authenticated permit > > That is VERY BAD. > > Your submission service appears to be an open relay. Change the final > 'permit' to 'reject' to fix that.
Note that the OP also has: smtpd_relay_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination For which there may not be an override in master.cf, in which case: # Or just empty mua_recipient_restrictions = permit is fine. Indeed Postfix would refuse to accept any mail if there's no "default reject" policy in one of relay/recipient restrictions, so likely the relay restrictions are reasonable. -- Viktor.