HTTPS traffic to Microsoft not captured

I’m trying to use Fiddler to capture traffic for a Microsoft Support case.  I’ve installed Fiddler, and I can see it work when browsing with Firefox, but I am unable to see HTTPS traffic which is being sent from my Java application.  I have attempted to install the Fiddler certificate – it seems to be present – but I still don’t see the traffic.

 

Here are the details of my setup:

I work on a Windows laptop. On this laptop, I have an Ubuntu 20.04 Linux VM running in VMWare.  My application runs here. My Windows laptop is logged into my corporate network over a VPN. I’ve installed Fiddler on Linux. I’ve downloaded and installed the Fiddler certificate as instructed here:  https://docs.telerik.com/fiddler-everywhere/get-started/quickstart-linux#capturing-secure-traffic

 

This refers to a “system proxy” – I don’t know much about this, or whether any changes need to be made to that.

 

I’m trying to capture traffic that goes over TLS to a few Microsoft APIs (login.microsoftonline.com, graph.microsoft.com).

 

I don’t see any errors in the logs from Fiddler, and I’m really not sure what I might be doing wrong.  I haven’t found anything useful for this problem on stackoverflow or in the Fiddler discussion pages.

 

-Mark

1 Comment

Capturing traffic from Firefox means that the Fiddler Everywhere proxy works as expected and that you probably need to configure your Java app to respect the system proxy. Refer to this article for more instructions on how to configure the Java application to respect the Fiddler proxy and certificate:


Alternative approaches can be found here but note that you will have to change the proxy port to 8866, as the instructions are written for Fiddler Classic, which uses 8888.