我们已经为我们的域配置了 SPF、DKIM 和 DMARC 记录，它们运行良好。我们来自 Gmail、Hotmail、Yahoo 的 DMARC 报告也证实了这一点。
然而，就在上周，我们的一位 (Gmail) 用户引起了我们的注意，一封来自我们域中的欺骗性电子邮件地址的欺诈性电子邮件。
查看电子邮件标头后，我们意识到 Gmail 根本没有启动 DMARC 检查，并且电子邮件到达了用户的收件箱。Gmail 仅执行了已通过的 SPF 检查，因为该检查是在信封 FROM 标头域上执行的。
电子邮件标头（已编辑识别详细信息）如下所示：
Delivered-To: redacted@gmail.com
Received: by 10.28.167.23 with SMTP id q23csp326872wme;
Mon, 20 Feb 2017 23:53:04 -0800 (PST)
X-Received: by 10.36.147.1 with SMTP id y1mr22192213itd.34.1487663583976;
Mon, 20 Feb 2017 23:53:03 -0800 (PST)
Return-Path: <redacted@fraudulentdomain.net>
Received: from server2.fraudulentdomain.net (server2.fraudulentdomain.net. [144.X.Y.Z])
by mx.google.com with ESMTP id i196si19658513ioi.78.2017.02.20.23.53.03
for <redacted@gmail.com>;
Mon, 20 Feb 2017 23:53:03 -0800 (PST)
Received-SPF: pass (google.com: domain of redacted@fraudulentdomain.net designates 144.X.Y.Z as permitted sender) client-ip=144.X.Y.Z;
Authentication-Results: mx.google.com;
spf=pass (google.com: domain of redacted@fraudulentdomain.net designates 144.X.Y.Z as permitted sender) smtp.mailfrom=redacted@fraudulentdomain.net
Received: by server2.fraudulentdomain.net (Postfix, from userid 330)
id 385716C165; Tue, 21 Feb 2017 08:53:03 +0100 (CET)
To: redacted@gmail.com
Subject: Some Subject
From: My Service <spoofed@mydomain.com>,
"MIME-Version:1.0"@server2.fraudulentdomain.net
Content-type: text/html; charset=iso-8859-1
Message-Id: <20170221075303.385716C165@server2.fraudulentdomain.net>
Date: Tue, 21 Feb 2017 08:53:03 +0100 (CET)
为什么 Gmail 没有启动 DMARC 检查而只是执行了 SPF 检查？是否与具有 2 个值的 Display FROM 标头有关？