Today received a mail who appears to be coming from a account from our domain, but when mail header is analized it comes from another server and user.
Mail arrived from a real owned domain directed to a real account on my owned domain.
How is this possible?
How i can avoid this problem?
Mail Header edited partially for security reasons:
Received: from SN6PR06MB4765.namprd06.prod.outlook.com (2603:10b6:805:ca::39)
by SN6PR06MB4765.namprd06.prod.outlook.com with HTTPS via
SN6PR16CA0062.NAMPRD16.PROD.OUTLOOK.COM; Thu, 24 Jan 2019 17:27:23 +0000
Received: from DM6PR06CA0047.namprd06.prod.outlook.com (2603:10b6:5:54::24) by
SN6PR06MB4765.namprd06.prod.outlook.com (2603:10b6:805:9e::23) with Microsoft
SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id
15.20.1558.17; Thu, 24 Jan 2019 17:27:21 +0000
Received: from BL2NAM02FT029.eop-nam02.prod.protection.outlook.com
(2a01:111:f400:7e46::204) by DM6PR06CA0047.outlook.office365.com
(2603:10b6:5:54::24) with Microsoft SMTP Server (version=TLS1_2,
cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1558.16 via Frontend
Transport; Thu, 24 Jan 2019 17:27:20 +0000
Authentication-Results: spf=pass (sender IP is 66.96.184.5)
smtp.mailfrom=eigbox.net; **myrealdomain.com**; dkim=none (message not signed)
header.d=none;**myrealdomain.com**; dmarc=fail action=oreject
header.from=**myrealdomain.com**;compauth=fail reason=000
Received-SPF: Pass (protection.outlook.com: domain of eigbox.net designates
66.96.184.5 as permitted sender) receiver=protection.outlook.com;
client-ip=66.96.184.5; helo=bosmailout05.eigbox.net;
Received: from bosmailout05.eigbox.net (66.96.184.5) by
BL2NAM02FT029.mail.protection.outlook.com (10.152.77.100) with Microsoft SMTP
Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id
15.20.1558.11 via Frontend Transport; Thu, 24 Jan 2019 17:27:20 +0000
Received: from bosmailscan09.eigbox.net ([10.20.15.9])
by bosmailout05.eigbox.net with esmtp (Exim)
id 1gmime-0001Df-40
for **realuserindomain@myrealdomain.com**; Thu, 24 Jan 2019 12:27:20 -0500
Received: from [10.115.3.33] (helo=bosimpout13)
by bosmailscan09.eigbox.net with esmtp (Exim)
id 1gmime-00083z-09
for *realuserindomain@myrealdomain.com**; Thu, 24 Jan 2019 12:27:20 -0500
Received: from bosauthsmtp06.yourhostingaccount.com ([10.20.18.6])
by bosimpout13 with
id UHSH1z00E07rX7u01HSLMQ; Thu, 24 Jan 2019 12:26:20 -0500
X-EN-SP-DIR: OUT
X-EN-SP-SQ: 1
Received: from [190.146.197.219] (port=9098 helo=10.1.29.91)
by bosauthsmtp06.eigbox.net with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256)
(Exim)
id 1gmilb-0004Nx-Pw
for *realuserindomain@myrealdomain.com**; Thu, 24 Jan 2019 12:26:17 -0500
Date: Thu, 24 Jan 2019 12:26:21 -0500
**From: Presidencia <userinmyrealdomain@myrealdomin.com>**
Thanks in advance.