Using Fiddler, is it possible to monitor the traffic of the Telegram Desktop application in order to auto-save messages/photos/videos to local storage as they are received?

 

I know that it is possible to do this using the telegram API, but for the educational purpose of studying traffic monitoring through Fiddler, I would like to explore this unusual approach.

I installed Fiddler Classic some time ago on recommendation from a friend for investigating an issue I was having which has since been resolved,. However I now have a problem where when I close (or even completely uninstall) Fiddler Classic, some apps on my PC (eg. Adobe Creative Cloud and Epic Games) can not access the internet. All other applications (eg. Chrome, Steam, Rambox, etc) still function perfectly fine. Even though this is the case, I have confirmed that the proxy settings are correct (ie. disabled) when Fiddler Classic is not running so I am not sure why this is occuring.

I no longer have a need for Fiddler Classic and I would like to remove it from my PC but this is obviously stopping me from being able to do so. Does anybody have any suggestion?

Request from a Python code only works if Fiddler is open and capturing traffic. If I turn off capturing or close Fiddler Everywhere (for Mac) request response is always 403 (Forbidden). Probably something related to certificates. Can you help me on this?

I user fiddler classic as proxy and it works well.

i try to use it to access https://link.springer.com/ iget this:

System.Security.SecurityException Failed to negotiate HTTPS connection with server.fiddler.network.https> HTTPS handshake to link.springer.com

This is because fiddler classic does not yet support tls 1.3. When will fiddler classic be updated to support tls1.3?

thanks so much!

i have installed Bouncy Castle, but cannot change the generator as Bouncy Castle

 

OMG! No offense. but the font-size is so small and blurry that it makes this app worthless.  Too bad I gotta ditch this app.

During the installation of the app I get this screen saying Unhandled Exception:System.IO.FileNotFoundException:Could not load the file or assembly system.core. I also got another error saying "Please add Fiddler classic installion directory to path environment variable". I have included the image. But the app is installed and after that when I try to launch it is not running.  Nothing happens when I run the app.

I am using windows 11 and have Dot net framework 3.5 and and 4.8 installed. Their features are turned on. I tried moving the system.core file from dot net framework to where fiddler is installed, it didn't work.

I have a pcap file and an sslkeylogfile.txt i was able to open the pcap file and add the decryption keys from the log file to wireshark.

But in Fiddler im only able to import the pcap file but can not import the sslkey file

V4.1.2 don't run my macos，I need old version，please help me.

Hey Nick,

Love the software. Could really help us in an upcoming project. One question. I've been playing with the HTTPS decryption. I've installed BouncyCastle and I'd like to run that. When the Root CA is generated, as you will know, DO_NOT_TRUST is displayed as the CAs name. This would be no good in the instance we needed to deploy Fiddler at the clients' site under our guidance. I've found some settings (prefs) namely; fiddler.CertMaker.Root.ExtraParams and fiddler.CertMaker.EE.ExtraParams. I've spent hours before reaching out. I found a bug using one of the other encryption systems, where the Root pref was read into the EE variable in the system, and also vice versa, the EE pref showed up as the Root setting. I've tried passing the -n argument along with the formatted distinguished name. I've had no success, hence why I am reaching out to you. Can you please explain to me how to change the Root CA Common names for the PoC setup Im building for an upcoming project?

Love the software and documentation. It's really great.

Warm regards

Dean