I receive fake emails with several addresses in "From:". For example:
Return-Path: <email@example.com> X-Original-To: Delivered-To: Received-SPF: None (mailfrom) identity=mailfrom; client-ip=220.127.116.11; helo=peewee.webdevworld.com; firstname.lastname@example.org; receiver=<UNKNOWN> Received: from peewee.webdevworld.com (peewee.webdevworld.com [18.104.22.168]) ... Date: Tue, 13 Nov 2018 10:51:03 -0500 From: John Sample <email@example.com> <firstname.lastname@example.org> To:
The email seems sent by email@example.com (It is one of our real contacts) but the real sender is firstname.lastname@example.org
I want to deny emails with multiple addresses in the FROM field. What tool or postfix parameter can I use to stop this?
I use Postfix 3.3 + ESET Mail Security + RBL + SPF