Fraudulent signups or spam?

Target acquires email addresses, exposing more customers to data breaches

• laura
• Jan 16, 2014

• Best Practices

As most folks now know hackers broke into Target systems last December and stole financial and other data from 110 million customers. Target has been responding to this breach reasonably well. They’ve been notifying customers that were affected and they’re providing credit monitoring for affected individuals. They seem to be totally on top of protecting their customer’s data and privacy.
Mostly.
They seem to be purchasing or otherwise acquiring email addresses from at least one major retailer in order to send out notifications about the breach to customers that never gave them email addresses. Yes, even those of us who chose not to give Target email addresses are receiving email from them.
I understand Target’s drive to contact affected users. I even appreciate that. What I don’t appreciate is that Target appears to be compromising my security in order to notify me my security was compromised. The data of mine that was compromised at Target would be credit card and possibly address information. My email address was not part of the compromise. So what does Target do? They go and acquire my email address from a third party.
Their solution to the compromise is collecting more data that is vulnerable to compromise from unrelated third parties? I’m not sure this is the most consumer friendly thing Target could do. In my case, Target sent mail to an address I’ve only given to Amazon. That means I now need to worry about my Amazon account security, on top of everything else.
Ironically, the email sent by Target tells me that I can click a link and get free credit monitoring. Then the email goes on to tell me the following:

• Never share information with anyone over the phone, email or text, even if they claim to be someone you know or do business with. Instead, ask for a call-back number.
• Delete texts immediately from numbers or names you don’t recognize.
• Be wary of emails that ask for money or send you to suspicious websites. Don’t click links within emails you don’t recognize.

Don’t click links within emails I don’t recognize? You mean like the one you just sent me? With a link to a credit monitoring website?
I appreciate the notice. I don’t appreciate is that Target went out of their way to collect more information about me than I actually gave them. I am now worried about Amazon’s security as well. How did Target get an address only provided to Amazon? I don’t appreciate that my efforts to keep my information secure (not providing email address to Target) was undermined by Target themselves.
The full text of the email, with the relevant headers (munged slightly for privacy) is under the cut, if anyone is interested.

Tagged Email Addresses

• steve
• Jul 12, 2010

• Best Practices , Industry

Sept 17, 2019: Shutting down comments on this post because we cannot help you recover any email account and I am concerned about the number of people who are providing PII (including phone numbers, credit card numbers!!! and email addresses) in the comments. 

Clickthrough forensics

• steve
• Dec 7, 2015

• Technical

When you click on a link in your mail, where does it go? Are you sure?
HTTP Redirects
In most bulk mail sent the links in the mail aren’t the same as the page the recipients browser ends up at when they click on it. Instead, the link in the mail goes to a “click tracker” run by the ESP that records that that recipient clicked on this link in this email, then redirects the recipients web browser to the link the mail’s author wanted. That’s how you get the reports on how many unique users clicked through on a campaign.
In the pay-per-click business that’s often still not the final destination, and the users browser may get redirected through several brokers before ending up at the final destination. I walked through some of this a few years ago, including how to follow link redirection by hand.
HTTP Forensics
Evil spammers sometimes deploy countermeasures against that approach, though – having links that will only work once or twice, or redirects that must be followed within a certain time, or javascript within an intermediate page or any of a bunch of other evasions. For those you need something that behaves more like a web browser.
For serious forensics I might use something like wireshark to passively record all the traffic while I interact with a link from inside a sandboxed browser. That’s not terribly user-friendly to use or set up, though, and usually overkill. It’s simpler and usually good enough to use a proxy to record the web traffic from the browser. There are all sorts of web proxies, used for many different things. What they have in common is that you configure a web browser to talk to a proxy and it’ll send all requests to the proxy instead of to the actual website, allowing the proxy to make any changes it wants as it forwards the requests on and the results back.
For investigating what a browser is doing the most useful proxies are those aimed at either web developers debugging web apps or crackers penetration testers compromising web apps. Some examples are Fiddler (Windows), Cellist (OS X, commercial), mitmdump (OS X, linux, Windows with a little work), Charles (anything, commercial) or ZAP (anything).
I’m going to use mitmdump and Firefox. You don’t want to use your main browser for this, as the proxy will record everything you do in that browser while you have it configured – and I want to keep writing this post in Safari as I work.