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Sniffing tracking pixels?

Problem: I'm trying to check if a tracking pixel is firing on a page. We installed third party tracking mechanism (Mediaplex) and I need to make sure it's working properly. This mechanism is just a bit of code that looks something like this:

This bit of code sits inside a body tag.

Question: Can Wireshark help me see if the Mediaplex tag is sending data out? If yes, how please? I'm a total noon when it come to this. :)

tracking pixel

asked 17 Jan '14, 13:29

Whatatrip
11●1●1●3
accept rate: 0%

edited 17 Jan '14, 14:19

One Answer:

Can Wireshark help me see if the Mediaplex tag is sending data out?

yes. Just start Wireshark and let it capture all traffic of your client (see the docs how to do that).

Then start a browser and load the page that has the mediaplex code included. If the browser loads the link in the iframe, you will see a SSL/HTTPS connection from your client to secure.img-cdn.mediaplex.com.

HOWEVER: the connection is encrypted, so you will neither see the URL (you mentioned above) nor any other data in that connection.

There are ways to decrypt the connection, if you browser exports the session keys. However, that's rather complicated for a 'noon' (as you said).

So, in your case I would recommend to check if the mediaplex code works, with one of the following methods

ask the vendor (mediaplex) if it works and/or check your mediaplex logs
use Fiddler2 to intercept SSL traffic of your client. Then you will be able to see the requests and contents of the mediaplex connections.
use some browser developer tools (Firebug or similar) to monitor requests of your client

Regards
Kurt

answered 21 Jan '14, 04:44

Kurt Knochner ♦
24.8k●10●39●237
accept rate: 15%

edited 21 Jan '14, 04:45