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从 gsmtp 退回邮件 - 奇怪的邮件路径

tag-icon • tag-icon email smtp email-server exim smtp-headers
从 gsmtp 退回邮件 - 奇怪的邮件路径

请考虑以下从退回给原始发件人的邮件中获取的电子邮件标头。多部分退回邮件还包含原始发件人和预期收件人之间的通信记录（明文 + HTML），我已将其删除。

问题是：这条消息是怎么到达 Gmail 的？

很长一段时间以来，我都以为自己对 (E)SMTP 非常熟悉，但现在似乎不再如此了。假设这不是假退回，我只能猜测是指定了不同的信封收件人（发件人被黑客入侵了？），或者收件人的 MTA 上涉及一些密件抄送映射或别名功能。

以下实体已被替换为其各自的占位符：

  • %original sender%- 实际将退回邮件转发给%intended-recipient%

  • %intended recipient%- 担心自己安全的人，因为 %original-sender% 转发了这封退回邮件

  • %totally unrelated%@gmail.com- 某人的电子邮件地址，%original-sender% 和 %intended-recipient% 均未与其通信。

    发件人：邮件投递系统 [mailto:Mailer-Daemon@]
    发送时间：2013 年 10 月 17 日星期四下午 1:22
    收件人：%原始发件人%
    主题：邮件投递失败：将邮件退回给发件人

该消息是由邮件传递软件自动创建的。

您发送的邮件无法递送给一个或多个收件人
。这是一个永久性错误。以下地址失败：

**%totally unrelated%** @gmail.com  
SMTP error from remote mail server after end of data:  
host gmail-smtp-in.l.google.com [2a00:1450:4001:c02::1b]:  
550-5.7.1 [ **%currently unreachable IPv6 address%** 16] Our system has detected  
550-5.7.1 that this message does not meet IPv6 sending guidelines regarding PTR  
550-5.7.1 records and authentication. Please review  
550-5.7.1 https://support.google.com/mail/?p=ipv6_authentication_error for more  
550 5.7.1 information. u47si3796594eel.284 - gsmtp  
  
  
------ This is a copy of the message, including all the headers. ------  
  
Return-path: <**%original sender%**>  
  
Received:  
from **%MX of intended recipient%** ([ **%IP address of MX of intended recipient%** ])  
by **%another MTA in the network of recipient's ISP%** with esmtp (Exim 4.63 #1 (Debian))  
id 1VWleU-0006QW-Pl  
from < **%original sender%** >  
for < **%totally unrelated%** @gmail.com>; Thu, 17 Oct 2013 13:22:02 +0200  
  
Received:  
from **%MTA of sender's ISP%**([**%IP of MTA of sender's ISP%**])  
by **%MX of intended recipient%** with esmtp (Exim 4.69 #1 (Debian))  
id 1VWleU-0004oq-JG  
for <**%intended recipient%**>; Thu, 17 Oct 2013 13:22:02 +0200  

Received:  
from **%sender's hostname%** (**%sender's PTR%**[ **%sender's IP%** ])  
by **%MTA of sender's ISP%**(Postfix) with ESMTPA  
id 3d0nyG0hwJz1741X  
for <**%intended recipient%**>; Thu, 17 Oct 2013 13:21:41 +0200 (CEST)  
  
From: **%sender's name encoded%**  <**%original sender%**>  
To: **%intended recipient's name encoded%** <**%intended recipient%**>  
References: <000c01cecb17$d9321ef0$8b965cd0$@tlh>  
In-Reply-To: <000c01cecb17$d9321ef0$8b965cd0$@tlh>  
Subject: **%subject line encoded%**
Date: Thu, 17 Oct 2013 13:21:41 +0200  
Message-ID: <00b701cecb2b$0dfd9d40$29f8d7c0$@**%sender's domain%**>  
MIME-Version: 1.0  
Content-Type: multipart/alternative;  
        boundary="----=_NextPart_000_00B8_01CECB3B.D1866D40"  
X-Mailer: Microsoft Outlook 14.0  
Thread-Index: AQGITggPsq7UFiUmFwcnkdC2rH3HB5qFuXTQ  
Content-Language: tlh  
  
This is a multipart message in MIME format.

答案1

最终用户正在通过 MTA（如 /etc/aliases）转发他们的电子邮件。

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