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MITM certificate uses SHA1 - Now considered deprecated by Chrome

As of recently, Chrome started to alert about sites that have SHA1 SSL certificates (and if they have HSTS, blocks them completely). Because Fiddler's self-signing certs use SHA1, that makes it problematic to use fiddler with chrome.
  • Guest
  • Apr 9 2017
  • Needs review
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  • Eric Lawrence commented
    April 10, 2017 18:43

    Fiddler, in general, does not use SHA1 in its certificates unless you haven't updated it in many years, or you've set an obscure preference. 

    On what platform are you having a problem? Which certificate maker are you using (see the blue link in Tools > Fiddler Options > HTTPS).

    See for background. Using the "Reset Fiddler certificates" button in the Action button is probably enough to fix you up.