First of all I'll say that I've investigated it deeply.

I used to have fiddler  4 , earlier versions and never updated.

When my computer turned to sleep , I was able to wake it by trying to rdp it.

The connection itself to rdp - woke the computer ( via network card) and the computer awoke ,and then I could connect to it.

this feature is called "wake on link".

After installing fiddler ( latest version) , suddenly my computer won't wake up from sleep when trying to connect to pc.

at first I didn't know what whet wrong and then I started uninstalling latest installed programs

When I uninstalled fiddler , it started waking  the computer

So I don't know what's you've done in the last version , but it f*s some other functionalities.

please fix it.

I'm working on an open-source Fiddler Classic extension to search the Session log (history). I'm not aware of such an extension and the lack of a search feature for the log entries always bothered me.

My current implementation already works, it searches the history listview, but it can only search in the text displayed in the listview itself because additional data is only available in the HistoryItem instances, attached to the Tag property of each list item.

Since HistoryItem is internal, I cannot access this class. I could work around this by using reflection but the internal classes of Fiddler are all obfuscated so, at the very least, my source code would look very strange and unmaintainable.

Please make HistoryItem public so it'd be accessible and un-obfuscated.

Fiddler currently does not validate that the Fiddler Trusted Root Certificate is not expired when generating certificates, and it generates certificates that have an expiration that is after the expiration of the root certificate. These certificates will not work because the browser validates the expiration of each certificate in the chain.

Browsers have a poor error message for this case and will imply that the Site's certificate is expired when it's actually the ROOT that expired.

When it loads the root certificate, Fiddler should verify that it is not expired, and if it is, it should trigger the RESET ALL CERTIFICATES flow to help unblock the user from this situation.

It should also be changed such that the root certificate is valid for MUCH longer than the site certificates (e.g. 5 years for the root) so this is less likely to happen.

(If you look in the forums, users are hitting this problem and they are not sure why or how to fix it.)

If I add a filter to hide something like /teams-modular-packages/ after closing fiddler classic and opening new file filter shows as active but is not working. I need to explicit remove filter and add it again. I would understand that filter wouldn't work accross sessions if filters were removed but they aren't and always showing in bottom left corner. This can be easily reproducible. (in this repro i have imported HAR file, not done a live capture)

 

The error messages pops up on Windows 10 version 1703.  Fiddler installs and runs with not issues on Windows 10 version 1607.

I often have to locally save a lot of responses manually.

My workflow is:
• Open a .saz file

• Search for a particular request

• Save the response locally.

 

For that, I always have to manually click the "Response body is encoded. Click to decode." Button.

Fiddler Classic doesn't have a feature to automatically decode the selected request's response body.

 

So if I don't pay attention, and skip a step, I will store an encoded response body, without ever noticing it. Which can cause trouble later, since these files are then sent to my customer. And the customer could randomly check the files.

 

I need a toggle in Fiddler, that automatically decodes the selected request's response body.

Today, Fiddler exposes these two events to handle scenarios where the user is saving or loading a SAZ file.

        /// fires just before a SAZ file is saved
        public static event EventHandler<WriteSAZEventArgs> OnSaveSAZ;

        /// fires just after a SAZ file is loaded
        public static event EventHandler<ReadSAZEventArgs> OnLoadSAZ;

Equivalent event handlers should be created for the scenario where a user is Importing content into the Sessions list (e.g. using NetLog import or HAR import, etc). Otherwise, developers must undertake cumbersome workarounds to detect that a list of Sessions has been created/loaded from a file import, if, say, they wish to perform processing on those imported Sessions (adding custom properties or changing the display properties in the Session list).

Would really appreciate a proper machine based installation again, user-based installs are difficult to manage in corporate/enterprise environments & the psuedo machine install of redirecting install folder & creating new shortcuts isn't great, especially if as you mention yourself extensions wont work.

I understand the advantage of not needing admin rights to install programs, but surely most of the targeted audience for this application would either A) have admin rights, or B) be in a managed environment with deployment software in use (and potentially white-listing/App Control software preventing unauthorized apps to run anyway)

Hi Team,

We wanted to use Fiddler Classic and when we send for Security Scanning, its flagged as Malicious. From your end, do you have confirmation like it would be false positive. Attached the screenshot where it was flagged as Malicious.

Thanks.

I would be nice if Fiddler could decrypt zstandard compressed requests.

For legacy reasons, Fiddler logs the message "HTTPSLint> Warning: ClientHello record was {0} bytes long. Some servers have problems with ClientHello's greater than 255 bytes"

This message should be removed because at this point, effectively ALL clienthellos are over 500 bytes and basically all servers are okay with it.

(This message was only relevant around 2014 or so when longer clienthellos started becoming common)

When sending post data, -d option needs to ensure that the data does not start with an @

https://portswigger.net/research/the-curl-quirk-that-exposed-burp-suite-amp-google-chrome

 

BasicFormats.dll - cURLExport.cs

As noted in the Fiddler book,

Sessions rerouted from one hostname to another using the Host Remapping tool are rendered with a light blue background in the Web Sessions list. HTTPS Sessions that have been rerouted have the X-IgnoreCertCNMismatch and X-OverrideCertCN Session Flags set to avoid raising “Certificate Name Mismatch” errors.

However, there's a bug. In the HostsFile.cs code, there's are several places that look like:

            if (oS.isTunnel) {

                oS["x-overrideCertCN"] = oS.hostname;
                oS["X-IgnoreCertCNMismatch"] = "HOSTS-Ext";
            }

This usually works for browser traffic going through Fiddler (because the HTTPS handshake is typically conducted on the CONNECT tunnel). However, it doesn't work (and the user is spammed with cert error warnings) if the traffic is sent from Fiddler itself (e.g. via Composer or using the "Reissue requests" context menu item). 

The code should look like this:

            if (oS.isHTTPS || oS.isTunnel) {

                oS["x-overrideCertCN"] = oS.hostname;
                oS["X-IgnoreCertCNMismatch"] = "HOSTS-Ext";

           }

The .NET Framework has added support for TLS/1.3.

We should do the work to enable TLS/1.3 in Fiddler (it's very little additional work to add "Tls1.3" to the options dialog and the underlying code). 

This would be useful to compare a completed working trace versus a non-working trace, side by side and see what the difference in the traces are.

Hi,

I’m developing a .NetFramework extension for Fiddler and am finding an issue with clearing bold, italic, strikethrough on the session text in the session list when using “this.session.RefreshUI()”. I’d like to be able to see these changes occur upon a context menu item click, immediately within Fiddler, without having the reload the sessions or the application. I can see the session flags are removed from the session as expected, but the bold, italic, or strikethrough is not unset.

I’m aware there is an option to Mark, Unmark sessions, but this doesn’t fit integrate closely enough with the extension I am developing or do exactly what I would like.

I seem to have no issues with changing the UI-Backcolor or UI-Color and refreshing for the updates to be immediately seen.

I can set UI-Bold, UI-Italic, UI-Strikethrough, but I cannot unset these with RefreshUI().

Is this a bug? Is the RefreshUI() call not doing something for UI-Bold, UI-Italic & UI-Strikethrough which it does do for UI-BackColor and UI-Color?

Thanks,

Jeremy.

I will be very useful if the font can be configured separately. One font for the composer and results, and the other for the IDE.

If I change the FONT, all the IDE is updated, including the composers, but after RESTARING, the composer has the same font than before

Related issue: https://github.com/aws/aws-sdk-net/issues/2567

When sending multiple requests to the same domain, sometimes Fiddler alters the headers (in this case by duplicating the user-agent one), and in this case it causes a fail because a precomputed signature of the request does not match.

good morning 

i got error while capturing my app to auth.btxo.cn

=== Windows 10 64bit OS==

===Protocols I have enabled: <client>;ssl2;ssl3;tls1.0;tls1.1;tls1.2

====== Message from Fiddler v5.0.20211.51073  for .NET v4.6.1
HTTP/1.1 200 Connection Established
FiddlerGateway: Direct
Connection: close

fiddler.network.https> HTTPS handshake to 104.21.46.118 (for #17) failed. System.Security.Authentication.AuthenticationException A call to SSPI failed, see inner exception. < The message received was unexpected or badly formatted

Win32 (SChannel) Native Error Code: 0x80090326

 

Any help ??

Thank you

 

The fiddler response

A SSLv3-compatible ClientHello handshake was found. Fiddler extracted the parameters below.

Version: 3.3 (TLS/1.2)
Random: 65 58 47 1D 28 AB A2 68 50 33 C7 75 1E A4 8B F5 9D A6 FB A0 F9 D2 54 FA 93 D5 AE 78 E5 26 7D 89
"Time": 26/07/1985 15:35:49
SessionID: empty
Extensions: 
server_name auth.btxo.cn
status_request OCSP - Implicit Responder
supported_groups x25519 [0x1d], secp256r1 [0x17], secp384r1 [0x18]
ec_point_formats uncompressed [0x0]
signature_algs rsa_pss_rsae_sha256, rsa_pss_rsae_sha384, rsa_pss_rsae_sha512, rsa_pkcs1_sha256, rsa_pkcs1_sha384, rsa_pkcs1_sha1, ecdsa_secp256r1_sha256, ecdsa_secp384r1_sha384, ecdsa_sha1, dsa_sha1, rsa_pkcs1_sha512, ecdsa_secp521r1_sha512
SessionTicket empty
ALPN http/1.1
extended_master_secret empty
renegotiation_info 00
Ciphers: 
[C02C] TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
[C02B] TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
[C030] TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
[C02F] TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
[009F] TLS_DHE_RSA_WITH_AES_256_GCM_SHA384
[009E] TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
[C024] TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384
[C023] TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256
[C028] TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384
[C027] TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256
[C00A] TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA
[C009] TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
[C014] TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA
[C013] TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA
[009D] TLS_RSA_WITH_AES_256_GCM_SHA384
[009C] TLS_RSA_WITH_AES_128_GCM_SHA256
[003D] TLS_RSA_WITH_AES_256_CBC_SHA256
[003C] TLS_RSA_WITH_AES_128_CBC_SHA256
[0035] TLS_RSA_WITH_AES_256_CBC_SHA
[002F] TLS_RSA_WITH_AES_128_CBC_SHA
[000A] SSL_RSA_WITH_3DES_EDE_SHA

Compression: 
[00] NO_COMPRESSION

I've attached the raw HTTP response, copied directly from Fiddler. At lOperations[0].lRecords, you'll see that there are 2 records (arrays) and that each record contains 6 items, the last of which is an array. However, when I view the resonse using the JSON filter, the second of these arrays appears to contain only 5 items. I'm sure that the bug has something to do with the fact that the sub-array in the second array is an empty array, but it should display as an empty array, not as if it weren't there at all.