I made this little application mainly to point out how exceptionally easy it is for people to use a simple image to track you. The image shown above is a live example, but logging is disabled. Dynamic images like these are very common and found all over the internet. There's no way to tell if the dynamic image can track you, the only hint will be that the image source might point to a PHP file or other script file.
You've probably seen this type of thing before, this is nothing ground breaking or new, but not many people realize how easily an image can be used for tracking. One of the oldest and most common uses would be embedding these images into emails so that you know when someone opens and reads the email. Disabling HTML in your emails should fix that problem, but the internet in general is open to this problem.
Simply loading this tracker image triggers a PHP script, providing the full power and flexibility of PHP to access information about the client. Then that information can be used to generate a jpg image with PHP and sent back to the client. The tracker image then shows the client info such as their IP, Browser, OS, location etc. Obviously a real tracker image would be invisible or hidden, as to avoid attention.
You can also tell the PHP script to save all this data to a database or file, that's where the "tracking" part of this simple image comes into play. By using the [img] tag to embed it on a forum thread, the referral URL also lets you see which page the person was on when they viewed the image. That means it's very easy to link IP addresses to the pages people were looking at.
The amazing thing is that you can use almost any forum website to do this. Anyone could put these images in their signature or threads and there would be no way to tell if it's just a simple image, or if it's actually saving your information to a database every time you load it. This is a problem with nearly all forums and many other websites that allow users to post images.
First you need to acquire the GeoLite City binary file from here. Extract the files and you should get a file called GeoLiteCity.dat, put it inside the tracker_image folder (download image tracker and extract the folder and files if you haven't yet). I have provided the GeoLite Country binary file (GeoIP.dat) but I recommend you download the latest one from here. Just upload the files to your server and you're good to go, you don't need a database to use image tracker. You don't need to do anything else but I suggest you look at the config.php file, LOGGING IS DISABLED BY DEFAULT.).
Using the image in XHTML might look like this:
<img src="http://mywebsite.com/image_tracker/trackimg.php" />
Using it on a forum might look like this:
The GeoLiteCity.dat file is presently around 16MB in size, so most free hosts will not allow you to upload the file even in pure FTP.
License: GNU General Public License