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How to fix MOZILLA_PKIX_ERROR_MITM_DETECTED when we use SSL Bumping ?

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  • Last reply by cor-el

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Hi everyone,

We use a web proxy on my company and SSL Bumping for security reasons. In this case, all of HTTPS flow goes through the web proxy which acts as a certification authority. "Problem", Firefox (v67.x) detect a MITM attack despite the addition of the private CA well explained on the Mozilla FAQ (https://wiki.mozilla.org/CA/AddRootToFirefox). Obviously, it works with all other browsers.

Any ideas who can help ?

Hi everyone, We use a web proxy on my company and SSL Bumping for security reasons. In this case, all of HTTPS flow goes through the web proxy which acts as a certification authority. "Problem", Firefox (v67.x) detect a MITM attack despite the addition of the private CA well explained on the Mozilla FAQ (https://wiki.mozilla.org/CA/AddRootToFirefox). Obviously, it works with all other browsers. Any ideas who can help ?

All Replies (1)

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There are related security.pki.mitm prefs available on the about:config page. This pref should tell you the issuer of the certificate.

  • security.pki.mitm_canary_issuer

You can set this pref to true on the about:config page to import root certificate(s) from the Windows certificate store.

  • security.enterprise_roots.enabled = true

See also: