Issue with SSL decrypting

[Sebastian]

Im trying to decrypt the traffic from an application that used to work in the past months without any issue, however today when i tried to view the traffic i just saw this error in fiddler:

 

fiddler.network.https> HTTPS handshake to 104.28.25.251 (for #73) 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

 

Im not sure what im supposed to do here, seems like there is an issue with the Protocols that its using?

[Eric R | Senior Technical Support Engineer]

Hi Sebastian,

My apologies for the delay. This generally means the client hasn't trusted the Fiddler Root Certificate. Can you confirm the root certificate has been trusted? Note that this can also be reset using the Actions button in the HTTPS options like the below screenshot.

Alternatively, the Protocols may not be supported or enabled. Can you confirm which Protocols are set in the HTTPS options like the previous screesnhot?

Thank you and I look forward to your reply.

Regards,

Eric R | Senior Technical Support Engineer
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[Sebastian]

I didnt change anything on the setup and the program which is creating the traffic isnt updated aswell, all of a sudden it stopped working. Im pretty sure its some issue related to the Protocols / the website is behind cloudflare is that matters.

 

My Protocol list is similar to yours, so that should be fine?

[Eric R | Senior Technical Support Engineer]

Hi Sebastian,

From my limited understanding, Cloudflare does allow advanced security configurations. I recommend removing the Cloudflare integration and trying again. If it works without the integration, then it is likely that Cloudflare is the cause. 

If it doesn't work, then I recommend resetting the Certificates and performing the Decrypt HTTP Traffic steps again.

I hope this helps. Please let me know if you need any additional information. Thank you.

Regards,

Eric R | Senior Technical Support Engineer
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[Sebastian]

This issue still exists and im not able to disable/remove cloudflare here that simple. I dont get what changed since this setup worked just fine for months now and all of a sudden it broke / the decryption dosent work anymore.

[Nick Iliev]

Hello Sebastion,

 

Could it be that the site is using a deprecated version of TSL (like 1.0 or 1.1)? In any case, you could try the solution discussed in this forum thread.

 

Regards,
Nick Iliev
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[Sebastian]

Hey Nick, thanks for the response!

 

Semms like the link you posted is broken? It just redirects me to a blank page

[Nick Iliev]

Hi Sebastian,

 

Thanks for letting me know - indeed it was my bad! Here is the working link to the thread.

 

Regards,
Nick Iliev
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