MainSleaze

Last week Microsoft Store, a new online and retail outlet for computer giant Microsoft, started sending bulk email to an email address that never existed (a pure spamtrap), at a domain that has never had a legitimate email address. The ESP is ExactTarget.

In the past few months this email address has received increasing amounts of snowshoe spam mixed with occasional spam from legitimate companies and ESPs, types of spam that pure spamtraps rarely receive. When a single spamtrap lands on a legitimate company’s list, the reason is usually one of the following: a typoed subscription combined with failure to confirm new subscriptions, a database mishap (unlikely in this case), or a purchased list. When that spamtrap suddenly sees an uptick in both snowshoe spam and mainsleaze spam, however, the chances that it is on a list go up significantly.

Sending IP: 64.132.89.196

Spam Sample:

Actual Headers:

Received: from mta22.microsoftstoreemail.com (mta22.microsoftstoreemail.com [64.132.89.196])
        by <xxx> (Postfix) with ESMTP id <xxx>
        for <xxx>; Tue,  8 Nov 2011 07:xx:xx -0600 (CST)
DKIM-Signature: <xxx>
DomainKey-Signature: <xxx>
Received: by mta22.microsoftstoreemail.com (PowerMTA(TM) v3.5r15) id <xxx> 
        for <xxx>; Tue, 8 Nov 2011 07:xx:xx -0600 
        (envelope-from <bounce-<xxx>@bounce.microsoftstoreemail.com>)
From: "Microsoft Store" <microsoftstore@microsoftstoreemail.com>
To: <xxx>
Subject: Come see the new Windows Phones and holiday gift deals.
Date: Tue, 08 Nov 2011 07:xx:xx -0600
List-Unsubscribe: <mailto:leave-<xxx>@leave.microsoftstoreemail.com>
MIME-Version: 1.0
Reply-To: "Microsoft Store" <reply-<xxx>@microsoftstoreemail.com>
x-job: <xxx>
Message-ID: <xxx>
Content-Type: multipart/alternative;
        boundary="<xxx>"

Readable Email:

From: Microsoft Store <microsoftstore@microsoftstoreemail.com>
To: <spamtrap>
Subject: Come see the new Windows Phones and holiday gift deals.
Reply-To: Microsoft Store <reply-<xxx>@microsoftstoreemail.com>

It’s a great time to connect
Find everything to keep everyone in touch this season

Put people first with Windows Phone. Connect great people with great gifts. New Windows Phone devices put the people you care about first. And our expert-picked PCs with Windows Live connect you with family and friends around the world. Come in to the Microsoft Store today and walk out ready.
Visit a store: http://click.microsoftstoreemail.com/?<xxx>

Connect with us on Facebook. We’re sharing our best gift ideas with our favorite people (that’s you!) on Facebook. Like us for expert shopping advice, in-store events and upcoming chances to win free gifts – from us to you.
Want it all? Like us now: http://click.microsoftstoreemail.com/?<xxx>

<removed>

Microsoft Corporation
One Microsoft Way
Redmond, WA, 98052, USA

Share your enthusiasm and join our team. View all careers at the Microsoft Store: http://click.microsoftstoreemail.com/?<xxx>
Microsoft respects your privacy. Please view our online Privacy Statement: http://click.microsoftstoreemail.com/?<xxx>
If you would prefer to no longer receive promotional emails from the Microsoft Store, please click here to unsubscribe: http://click.microsoftstoreemail.com/?<xxx>
To set your contact preferences for other Microsoft communications, see the communications preferences section of the Microsoft Privacy Statement: http://click.microsoftstoreemail.com/?<xxx>