Hello,

I host remote FiddlerCore instance for remote debugging/etc. Obviously this is a bad idea, but I am trying to lockdown my instance from unauthorized users as an open proxy.

 

Ideally it would be through firewall/iptables, but since ip changes it is not very useful to me.

 

I would like to add proxy authentication, but iOS does not send "proxy-authorization"/"proxy-authentication" header, instead a proxy authentication challenge must be presented.

Is this possible with FiddlerCore? Any other tips for locking down this instance?

First of all, thanks a lot for this amazing framework. I have developed a small tool (c#) to intercept requests to a server and give them a local response using the LoadResponseFromFile method. This works nicely with both HTTP and HTTPS requests. Though, with HTTPS, I would have to let the first request pass to the server. I want to make it so that the tool would do without that. From my basic understanding, if I am not wrong, this has something to do with the original handshake. All subsequent requests can be handled without fuss.

Now, I went to the Fiddler tool and tries to trace this. The request that I cannot seem to handle, i.e. the first request, is displayed as:

200 HTTP Tunnel To x.x.x:443

where x.x.x is the server. The body size is 0. On Raw tab, I get:

HTTP/1.1 200 Connection Established

and some lines under it, Encrypted HTTPS traffic flows through this CONNECT tunnel. HTTPS Decryption is enabled in Fiddler, so decrypted sessions running in this tunnel will be shown in the Web Sessions list plus some other data.

Can you guide me in the right direction on how to handle those requests locally without having to rely on the server?

 

Regards and thanks.

When attempting to save a fiddler trace session file using FiddlerCap the 'Save Captures' dialog is unable to open and throws the following exception:

See the end of this message for details on invoking 
just-in-time (JIT) debugging instead of this dialog box.

************** Exception Text **************
System.Runtime.InteropServices.COMException (0x80040111): Creating an instance of the COM component with CLSID {C0B4E2F3-BA21-4773-8DBA-335EC946EB8B} from the IClassFactory failed due to the following error: 80040111 ClassFactory cannot supply requested class (Exception from HRESULT: 0x80040111 (CLASS_E_CLASSNOTAVAILABLE)).
   at System.Windows.Forms.SaveFileDialog.CreateVistaDialog()
   at System.Windows.Forms.FileDialog.RunDialogVista(IntPtr hWndOwner)
   at System.Windows.Forms.CommonDialog.ShowDialog(IWin32Window owner)
   at FiddlerCap2.frmMain.(Object , EventArgs ) in C:\JenkinsHome\jobs\FiddlerCapReleaseBuild\workspace\FiddlerCap\FiddlerCap\MainForm.cs:line 214
   at System.Windows.Forms.Control.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
   at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ButtonBase.WndProc(Message& m)
   at System.Windows.Forms.Button.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)


************** Loaded Assemblies **************
mscorlib
    Assembly Version: 4.0.0.0
    Win32 Version: 4.7.3110.0 built by: NET472REL1LAST_C
    CodeBase: file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/mscorlib.dll
----------------------------------------
FiddlerCap
    Assembly Version: 4.6.20182.28033
    Win32 Version: 4.6.20182.28033
    CodeBase: file:///C:/Windows/SysWOW64/config/systemprofile/Desktop/FiddlerCap/FiddlerCap.exe
----------------------------------------
System.Windows.Forms
    Assembly Version: 4.0.0.0
    Win32 Version: 4.7.3056.0 built by: NET472REL1
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Windows.Forms/v4.0_4.0.0.0__b77a5c561934e089/System.Windows.Forms.dll
----------------------------------------
System
    Assembly Version: 4.0.0.0
    Win32 Version: 4.7.3056.0 built by: NET472REL1
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System/v4.0_4.0.0.0__b77a5c561934e089/System.dll
----------------------------------------
System.Drawing
    Assembly Version: 4.0.0.0
    Win32 Version: 4.7.3056.0 built by: NET472REL1
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Drawing/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll
----------------------------------------
System.Configuration
    Assembly Version: 4.0.0.0
    Win32 Version: 4.7.3056.0 built by: NET472REL1
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Configuration/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll
----------------------------------------
System.Core
    Assembly Version: 4.0.0.0
    Win32 Version: 4.7.3110.0 built by: NET472REL1LAST_C
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Core/v4.0_4.0.0.0__b77a5c561934e089/System.Core.dll
----------------------------------------
System.Xml
    Assembly Version: 4.0.0.0
    Win32 Version: 4.7.3056.0 built by: NET472REL1
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Xml/v4.0_4.0.0.0__b77a5c561934e089/System.Xml.dll
----------------------------------------

************** JIT Debugging **************
To enable just-in-time (JIT) debugging, the .config file for this
application or computer (machine.config) must have the
jitDebugging value set in the system.windows.forms section.
The application must also be compiled with debugging
enabled.

For example:

<configuration>
    <system.windows.forms jitDebugging="true" />
</configuration>

When JIT debugging is enabled, any unhandled exception
will be sent to the JIT debugger registered on the computer
rather than be handled by this dialog box.

Is there any way we can access client code, inner HTML or control events using Fiddler core?

I have Fiddler v5 set up on Windows 10. I have followed the instructions for capturing iOS traffic detailed here, http://docs.telerik.com/fiddler/configure-fiddler/tasks/ConfigureForiOS

When Windows is not on a VPN, I can capture the traffic from my iPhone 8 with iOS 12.1 via Manual proxy setting and port 8888. However, when I connect to a VPN (Pulse Secure Network Connect 8.3) and then start up Fiddler, running as Administrator, I can then no longer load web pages in Safari on my iPhone and Fiddler doesn't capture any iOS traffic.

On the Tools > Options > Connections settings, I do have "Monitor all connections" checked.

What could prevent the proxy from working while on the VPN?

Thanks,

Nate

From your website, I downloaded mono framework and fiddler-mac in SnowLeopard.

After installing mono and doing /Library/Frameworks/Mono.framework/Versions/4.6.2/bin/mozroots --import --sync, I extracted the zip file in the document folder. In terminal, cd to the folder and type mono Fiddler.exe, then following error occured:

exception inside UnhandledException handler: The type initializer for 'Fiddler.CONFIG' threw an exception.

[ERROR] FATAL UNHANDLED EXCEPTION: System.TypeInitializationException: The type initializer for 'System.Windows.Forms.WindowsFormsSynchronizationContext' threw an exception. ---> System.TypeInitializationException: The type initializer for 'System.Windows.Forms.ThemeEngine' threw an exception. ---> System.TypeInitializationException: The type initializer for 'System.Windows.Forms.ThemeWin32Classic' threw an exception. ---> System.TypeInitializationException: The type initializer for 'System.Drawing.KnownColors' threw an exception. ---> System.TypeInitializationException: The type initializer for 'System.Drawing.GDIPlus' threw an exception. ---> System.DllNotFoundException: /Library/Frameworks/Mono.framework/Versions/4.6.2/lib/libgdiplus.dylib
  at (wrapper managed-to-native) System.Drawing.GDIPlus:GdiplusStartup (ulong&,System.Drawing.GdiplusStartupInput&,System.Drawing.GdiplusStartupOutput&)
  at System.Drawing.GDIPlus..cctor () [0x000cc] in <1917aa1c39d94b1a91807b8cd9f03350>:0
   --- End of inner exception stack trace ---
  at System.Drawing.KnownColors..cctor () [0x0001a] in <1917aa1c39d94b1a91807b8cd9f03350>:0
   --- End of inner exception stack trace ---
  at System.Drawing.Color.get_AliceBlue () [0x00000] in <1917aa1c39d94b1a91807b8cd9f03350>:0
  at Fiddler.CONFIG..cctor () [0x00206] in <f7619d266c2c40b09be7fbc7f689415c>:0
   --- End of inner exception stack trace ---
  at System.Windows.Forms.ThemeVisualStyles..ctor () [0x00000] in <d5b72d15d4f7424c8a1538e3f19ec2e3>:0
  at System.Windows.Forms.ThemeEngine..cctor () [0x0002d] in <d5b72d15d4f7424c8a1538e3f19ec2e3>:0
   --- End of inner exception stack trace ---
  at System.Windows.Forms.SystemInformation.get_MenuAccessKeysUnderlined () [0x00000] in <d5b72d15d4f7424c8a1538e3f19ec2e3>:0
  at System.Windows.Forms.Control..ctor () [0x000ea] in <d5b72d15d4f7424c8a1538e3f19ec2e3>:0
  at (wrapper remoting-invoke-with-check) System.Windows.Forms.Control:.ctor ()
  at System.Windows.Forms.WindowsFormsSynchronizationContext..cctor () [0x00000] in <d5b72d15d4f7424c8a1538e3f19ec2e3>:0
   --- End of inner exception stack trace ---
  at System.Windows.Forms.Control..ctor () [0x00014] in <d5b72d15d4f7424c8a1538e3f19ec2e3>:0
  at System.Windows.Forms.ScrollableControl..ctor () [0x00000] in <d5b72d15d4f7424c8a1538e3f19ec2e3>:0
  at System.Windows.Forms.ContainerControl..ctor () [0x0000e] in <d5b72d15d4f7424c8a1538e3f19ec2e3>:0
  at System.Windows.Forms.Form..ctor () [0x00012] in <d5b72d15d4f7424c8a1538e3f19ec2e3>:0
  at ..SetStyle (System.Windows.Forms.ControlStyles flag, System.Boolean value) [0x00000] in <f7619d266c2c40b09be7fbc7f689415c>:0
  at (wrapper remoting-invoke-with-check) .:.ctor ()
  at Fiddler.frmViewer.‹• (System.String[] ˆ•) [0x0004a] in <f7619d266c2c40b09be7fbc7f689415c>:0
  at Fiddler.frmViewer.‡• (System.String[] ˆ•) [0x00016] in <f7619d266c2c40b09be7fbc7f689415c>:0

Looking for proper thread-safe way to find/log current amount of unique connections (i.e. 1 ip is 1 connection)

Trying to set up the proxy on my pixel.  Followed the instructions, able to get to the fiddler echo page from my phone and installed the cert.  When I configure my phone's wifi to use the proxy I see the requests go out in fiddler but the phone reports back Connected, no internet.  That makes all future network calls revert to the cell data connection.  Has anybody experienced this before?

Receiving the following error from CertMaker when running the demo program.

Starting FiddlerCore/4.6.20181.13826 (Ionic.Zip, Version=1.9.1.8, Culture=neutral, PublicKeyToken=edbe51ad942a3f5c)...
** LogString: Setting upstream gateway to none
** LogString: Created endpoint listening on port 8877
** LogString: Gateway: None
Hit CTRL+C to end session.
** LogString: Assembly 'C:\temp\deloitte-symphony-cff-legal-holds\Deloitte.Symphony.LegalHolds.Selfie\Deloitte.Symphony.LegalHolds.Selfie\bin\Debug\CertMaker.dll' did not specify a RequiredVersionAttribute. Aborting load of Certificate Generation module.
** LogString: /Fiddler.CertMaker> Using .?+? for certificate generation; UseWildcards=True.
** LogString: Created secure endpoint listening on port 7777, using a HTTPS certificate for 'localhost'

Hello,

Just wanted to start off by stating that I know there is another discussion about this called "Silent or unattended install options?" but I am unable to reply to that thread as I keep encountering an error when I try.

From this thread though, I found you can do a silent install with /S switch.

I also found from Simeon's post that you can install to a specific directory with /D=C:\Program Files\Fiddler.

My issue is that when using these switches together, I am not getting the correct result. I am deploying Fiddler (v5.0.20181.14850) via an APPLICATION. I also tried to deploy as a package but was also having issues.

FiddlerSetup.exe /S /D=C:\Program Files\Fiddler - looks like the silent install is working but then the install will fail with error 0x87D00324(-2016410844). There is a Fiddler folder within program files but the .exe was not installed.
FiddlerSetup.exe /D=C:\Program Files\Fiddler /S -Incur pop up window to walk through the instillation. The default directory on the install is correct, but it is not silent.

 

When trying to install via package, I am trying the following :

FiddlerSetup.exe /S /D=C:\Program Files\Fiddler

Issue is that it looks like it installs successfully, I can find it within C:\Program Files\Fiddler but the doesn't actually install Fiddler, seems like it just places the install within that directory.