Network request not seen in Charles

Question

I am trying to see network request done by an iPhone app so I can check what data is being sent. Or at least, how many requests it is doing. But when using Charles or Burp Suite on my Mac, it does not show any request outputs from this specific app. All other requests show, also from inside other apps. But this specific app does not register any requests at all, even when all data inside the app is reloaded. How is this possible? Are there other ways to do requests? And can they be registered?

Ron

Answer 1

Although this doesn't answer the original question, but as I found this page by googling "Charles doesn't see any requests", this might be helpful to others:

Check if you have VPN turned on

In my case I had WireGuard VPN enabled, and apparently, Charles can not see through it. I was able to get a clue about it by starting WireShark and noticing "WireGuard" in protocol field for all the received packets

Answer 2

The app was doing SOAP requests. Apparently Charles does not pick those up. I used Wireshark to investigate. That one did the trick.

Answer 3

If this app is making https requests, and you haven't configured your Charles instance to inspect https traffic, one single "unknown" request may be shown under the app's domain(s) in the "structure" tab, and no new requests will appear in the sequence tab when you reload.

In case you haven't configured the https proxy yet, here is a good short walkthrough: Monitor Google Analytics requests on an iPhone Application

In case you already are seeing other https requests, I would try disabling mobile data, and see if this app's calls appear then - just in case iOS was bypassing Charles because it caused the wifi connection to lag.