Trace data through a pixel by mail
Receive junk emails it is something very common. Advertising e-mails frequently reach all of us and end up in the Spam folder. Sometimes it is just that, annoying advertising, but at other times it can be a real danger and can be used by hackers to sneak malware or steal information.
In this sense, a technique widely used by cybercriminals is that of tracking through pixels. Basically they are tiny images, barely one pixel, capable of obtaining personal data, knowing if we have opened an email, etc. This is used by attackers to create a profile of us and even send us Spam or even include us on a list to carry out Phishing attacks and the like.
A tracking or tracking pixel can go unnoticed by the user. We open an email and we don’t really see if there is such a small image. It is not something as obvious as a larger file, a link in the text, etc.
The images they are also usually transparent. We are therefore facing a small 1px file inserted in the e-mail and that generally use the JPG, GIF or PNG format. They are three of the most common formats in images.
How a tracking pixel works
How does a tracking pixel work? Once the sender of that email has inserted it in the header or footer, when a user opens that email, they automatically send information through that pixel. You basically know if you have opened it or not.
With this they can know how many people have opened an email in a marketing campaign, but also obtain more personal data, such as the email provider we use, if there is really an active user behind that account, our name, etc. They could even know what our IP address is and, in this way, know where we are.
Now, beyond serving as a method to obtain information for marketing or even sending Spam, it also serves for a cybercriminal to obtain data. Might gather information of the network where we are connected, to know our data to send more personalized Phishing attacks, etc.
However, we must point out that nowadays more and more email providers have techniques to block these pixels. They would not open automatically with access to an email and thus makes it difficult to send information to attackers.
We must always recognize fake emails before falling into traps like this one we see with pixels. It is essential to know if we are facing an e-mail that can steal our data or serve as an entry point for attackers.