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Can´t open google and many other sites anymore. Error MOZILLA_PKIX_ERROR_MITM_DETECTED

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I can not open a lot of websites anymore. I get the error: "Diese Verbindung ist nicht sicher

Der Inhaber von www.google.com hat die Website nicht richtig konfiguriert. Firefox hat keine Verbindung mit dieser Website aufgebaut, um Ihre Informationen vor Diebstahl zu schützen.

Diese Website verwendet HTTP Strict Transport Security (HSTS), um mitzuteilen, dass Firefox nur über gesicherte Verbindungen mit ihr kommunizieren soll. Daher ist es nicht möglich, eine Ausnahme für dieses Zertifikat anzulegen."

Error Code: MOZILLA_PKIX_ERROR_MITM_DETECTED

P.S. I do not have "avg" installed.

Error-Detail: " https://www.google.com/

Ihre Verbindung wird durch einen TLS-Proxy kontrolliert. Deinstallieren Sie diesen falls möglich oder richten Sie Ihr Gerät so ein, dass es dem Stammzertifikat des TLS-Proxies vertraut.

HTTP Strict Transport Security: false HTTP Public Key Pinning: true

Zertifikatskette:


BEGIN CERTIFICATE-----

MIIEGDCCAwCgAwIBAgIIZTLNOfRhA1EwDQYJKoZIhvcNAQELBQAwgakxCzAJBgNV BAYTAlVTMRMwEQYDVQQIEwpDYWxpZm9ybmlhMRUwEwYDVQQKEwxac2NhbGVyIElu Yy4xFTATBgNVBAsTDFpzY2FsZXIgSW5jLjEzMDEGA1UEAxMqWnNjYWxlciBJbnRl cm1lZGlhdGUgUm9vdCBDQSAoenNjbG91ZC5uZXQpMSIwIAYJKoZIhvcNAQkBFhNz dXBwb3J0QHpzY2FsZXIuY29tMB4XDTE4MDgxNDA3NDg0N1oXDTE4MTAyMzA3Mzgw MFowaDELMAkGA1UEBhMCVVMxEzARBgNVBAgMCkNhbGlmb3JuaWExFjAUBgNVBAcM DU1vdW50YWluIFZpZXcxEzARBgNVBAoMCkdvb2dsZSBMTEMxFzAVBgNVBAMMDnd3 dy5nb29nbGUuY29tMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAwEUg YENMeOogwF2up5agb1UH3CLRMEcJeQTQeuPa6DaGtPwWImFCe1bmRefOZ94czYw9 BXp0t5D2+k9fSB6FMdnKEzdnbhXrIpGklivv0oPBJuu1hOsXAZxWw7ZoU/r9hLXQ x8mfmFFgM4adCL41ucWD+7/Zzpt78FGww29PdHakGb505qipu+ckyjVI3PblEkLa tnpZpL3L+ji28laiGnUt2GyzynMsu7KIHadseKi49nx/KaFK04kxB9pvbU2k5+ok 874GK4RXzzFg6QW9cc4vpReFDusND+bGyTBm14mPiXmhS8T5TS2Ol20kjgsBhOf+ PL+aDE1ZsNBWqo+TVwIDAQABo4GDMIGAMBMGA1UdJQQMMAoGCCsGAQUFBwMBMBkG A1UdEQQSMBCCDnd3dy5nb29nbGUuY29tMAwGA1UdEwEB/wQCMAAwQAYDVR0fBDkw NzA1oDOgMYYvaHR0cDovL2dhdGV3YXkuenNjbG91ZC5uZXQvenNjYWxlci16c2Ny bC0tNC5jcmwwDQYJKoZIhvcNAQELBQADggEBAAM+f3HD5PycBc78377Dz4oLHCDp z1BVkQg2mcAi7+2Em1r/8EOaGBHfIQSaY+e28wOkpCRI43Edo3Ej6/IUXlNspC14 KsPHCUpvIUJMNdcaENk4ZyAHmM/B8NvtEpR+4QNANBtee36So5E13IK0GdGbYZhQ 7w9TB0Ubp0QKanw474/pYXjjEMaWghAOvFpaZ1+aJbjckYUnfBN03EUGol7HlC6v oj74AinBWsmsX2eWvXmq5IWwfAgFXUJh0oF0/iTttujsMPZgFExZq8VHMOzqULUT q91GnJ9u4CH/HpdcU7WTH8iQc9Yae15i9qY0pfI+8mr6Ohiy4HjQ20tGkRI=


END CERTIFICATE-----
BEGIN CERTIFICATE-----

MIIEBDCCAuygAwIBAgICd3owDQYJKoZIhvcNAQELBQAwgaExCzAJBgNVBAYTAlVT MRMwEQYDVQQIEwpDYWxpZm9ybmlhMREwDwYDVQQHEwhTYW4gSm9zZTEVMBMGA1UE ChMMWnNjYWxlciBJbmMuMRUwEwYDVQQLEwxac2NhbGVyIEluYy4xGDAWBgNVBAMT D1pzY2FsZXIgUm9vdCBDQTEiMCAGCSqGSIb3DQEJARYTc3VwcG9ydEB6c2NhbGVy LmNvbTAeFw0xNTAxMDYyMjM2MTFaFw00MjA1MjMyMjM2MTFaMIGpMQswCQYDVQQG EwJVUzETMBEGA1UECBMKQ2FsaWZvcm5pYTEVMBMGA1UEChMMWnNjYWxlciBJbmMu MRUwEwYDVQQLEwxac2NhbGVyIEluYy4xMzAxBgNVBAMTKlpzY2FsZXIgSW50ZXJt ZWRpYXRlIFJvb3QgQ0EgKHpzY2xvdWQubmV0KTEiMCAGCSqGSIb3DQEJARYTc3Vw cG9ydEB6c2NhbGVyLmNvbTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEB AMBFIGBDTHjqIMBdrqeWoG9VB9wi0TBHCXkE0Hrj2ug2hrT8FiJhQntW5kXnzmfe HM2MPQV6dLeQ9vpPX0gehTHZyhM3Z24V6yKRpJYr79KDwSbrtYTrFwGcVsO2aFP6 /YS10MfJn5hRYDOGnQi+NbnFg/u/2c6be/BRsMNvT3R2pBm+dOaoqbvnJMo1SNz2 5RJC2rZ6WaS9y/o4tvJWohp1Ldhss8pzLLuyiB2nbHiouPZ8fymhStOJMQfab21N pOfqJPO+BiuEV88xYOkFvXHOL6UXhQ7rDQ/mxskwZteJj4l5oUvE+U0tjpdtJI4L AYTn/jy/mgxNWbDQVqqPk1cCAwEAAaM8MDowHQYDVR0OBBYEFIjA8eY/bmcEpkmt hk4IVRE8FK7rMAwGA1UdEwQFMAMBAf8wCwYDVR0PBAQDAgH+MA0GCSqGSIb3DQEB CwUAA4IBAQBN2YpxKTt37zbIFsSkdexLX15Edh+RFw57lIar/uHZ4EgnAmOJ/8DP EE09zSml31v78CMtE6xgUOsKg41k27DAsnk3rlywyniOoYMhTiiuw49xAMQ/KaSX CJuaOOJAnCVXc7pKFFqkF1QF+Skw36hGJaackBY9dQhuCPuw2Tg8sIzOi7v94Nrw C7NZAa4Cr3gWFiYkzVgDhmhoUR2UqZdStwHu2b4Ksro2OMllpWXE3k4rZgow3eBE LG1zF85OOTypgX/cYElYCdZViRJJyPupcPsHViMNIbQ7IBKOENGZsCipV/UJZiZI 6inggEPaaPEtF/3X+QdksYP7Wg643zF7


END CERTIFICATE-----

"

I can not open a lot of websites anymore. I get the error: "Diese Verbindung ist nicht sicher Der Inhaber von www.google.com hat die Website nicht richtig konfiguriert. Firefox hat keine Verbindung mit dieser Website aufgebaut, um Ihre Informationen vor Diebstahl zu schützen. Diese Website verwendet HTTP Strict Transport Security (HSTS), um mitzuteilen, dass Firefox nur über gesicherte Verbindungen mit ihr kommunizieren soll. Daher ist es nicht möglich, eine Ausnahme für dieses Zertifikat anzulegen." Error Code: MOZILLA_PKIX_ERROR_MITM_DETECTED P.S. I do not have "avg" installed. Error-Detail: " https://www.google.com/ Ihre Verbindung wird durch einen TLS-Proxy kontrolliert. Deinstallieren Sie diesen falls möglich oder richten Sie Ihr Gerät so ein, dass es dem Stammzertifikat des TLS-Proxies vertraut. HTTP Strict Transport Security: false HTTP Public Key Pinning: true Zertifikatskette: -----BEGIN CERTIFICATE----- MIIEGDCCAwCgAwIBAgIIZTLNOfRhA1EwDQYJKoZIhvcNAQELBQAwgakxCzAJBgNV BAYTAlVTMRMwEQYDVQQIEwpDYWxpZm9ybmlhMRUwEwYDVQQKEwxac2NhbGVyIElu Yy4xFTATBgNVBAsTDFpzY2FsZXIgSW5jLjEzMDEGA1UEAxMqWnNjYWxlciBJbnRl cm1lZGlhdGUgUm9vdCBDQSAoenNjbG91ZC5uZXQpMSIwIAYJKoZIhvcNAQkBFhNz dXBwb3J0QHpzY2FsZXIuY29tMB4XDTE4MDgxNDA3NDg0N1oXDTE4MTAyMzA3Mzgw MFowaDELMAkGA1UEBhMCVVMxEzARBgNVBAgMCkNhbGlmb3JuaWExFjAUBgNVBAcM DU1vdW50YWluIFZpZXcxEzARBgNVBAoMCkdvb2dsZSBMTEMxFzAVBgNVBAMMDnd3 dy5nb29nbGUuY29tMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAwEUg YENMeOogwF2up5agb1UH3CLRMEcJeQTQeuPa6DaGtPwWImFCe1bmRefOZ94czYw9 BXp0t5D2+k9fSB6FMdnKEzdnbhXrIpGklivv0oPBJuu1hOsXAZxWw7ZoU/r9hLXQ x8mfmFFgM4adCL41ucWD+7/Zzpt78FGww29PdHakGb505qipu+ckyjVI3PblEkLa tnpZpL3L+ji28laiGnUt2GyzynMsu7KIHadseKi49nx/KaFK04kxB9pvbU2k5+ok 874GK4RXzzFg6QW9cc4vpReFDusND+bGyTBm14mPiXmhS8T5TS2Ol20kjgsBhOf+ PL+aDE1ZsNBWqo+TVwIDAQABo4GDMIGAMBMGA1UdJQQMMAoGCCsGAQUFBwMBMBkG A1UdEQQSMBCCDnd3dy5nb29nbGUuY29tMAwGA1UdEwEB/wQCMAAwQAYDVR0fBDkw NzA1oDOgMYYvaHR0cDovL2dhdGV3YXkuenNjbG91ZC5uZXQvenNjYWxlci16c2Ny bC0tNC5jcmwwDQYJKoZIhvcNAQELBQADggEBAAM+f3HD5PycBc78377Dz4oLHCDp z1BVkQg2mcAi7+2Em1r/8EOaGBHfIQSaY+e28wOkpCRI43Edo3Ej6/IUXlNspC14 KsPHCUpvIUJMNdcaENk4ZyAHmM/B8NvtEpR+4QNANBtee36So5E13IK0GdGbYZhQ 7w9TB0Ubp0QKanw474/pYXjjEMaWghAOvFpaZ1+aJbjckYUnfBN03EUGol7HlC6v oj74AinBWsmsX2eWvXmq5IWwfAgFXUJh0oF0/iTttujsMPZgFExZq8VHMOzqULUT q91GnJ9u4CH/HpdcU7WTH8iQc9Yae15i9qY0pfI+8mr6Ohiy4HjQ20tGkRI= -----END CERTIFICATE----- -----BEGIN CERTIFICATE----- MIIEBDCCAuygAwIBAgICd3owDQYJKoZIhvcNAQELBQAwgaExCzAJBgNVBAYTAlVT MRMwEQYDVQQIEwpDYWxpZm9ybmlhMREwDwYDVQQHEwhTYW4gSm9zZTEVMBMGA1UE ChMMWnNjYWxlciBJbmMuMRUwEwYDVQQLEwxac2NhbGVyIEluYy4xGDAWBgNVBAMT D1pzY2FsZXIgUm9vdCBDQTEiMCAGCSqGSIb3DQEJARYTc3VwcG9ydEB6c2NhbGVy LmNvbTAeFw0xNTAxMDYyMjM2MTFaFw00MjA1MjMyMjM2MTFaMIGpMQswCQYDVQQG EwJVUzETMBEGA1UECBMKQ2FsaWZvcm5pYTEVMBMGA1UEChMMWnNjYWxlciBJbmMu MRUwEwYDVQQLEwxac2NhbGVyIEluYy4xMzAxBgNVBAMTKlpzY2FsZXIgSW50ZXJt ZWRpYXRlIFJvb3QgQ0EgKHpzY2xvdWQubmV0KTEiMCAGCSqGSIb3DQEJARYTc3Vw cG9ydEB6c2NhbGVyLmNvbTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEB AMBFIGBDTHjqIMBdrqeWoG9VB9wi0TBHCXkE0Hrj2ug2hrT8FiJhQntW5kXnzmfe HM2MPQV6dLeQ9vpPX0gehTHZyhM3Z24V6yKRpJYr79KDwSbrtYTrFwGcVsO2aFP6 /YS10MfJn5hRYDOGnQi+NbnFg/u/2c6be/BRsMNvT3R2pBm+dOaoqbvnJMo1SNz2 5RJC2rZ6WaS9y/o4tvJWohp1Ldhss8pzLLuyiB2nbHiouPZ8fymhStOJMQfab21N pOfqJPO+BiuEV88xYOkFvXHOL6UXhQ7rDQ/mxskwZteJj4l5oUvE+U0tjpdtJI4L AYTn/jy/mgxNWbDQVqqPk1cCAwEAAaM8MDowHQYDVR0OBBYEFIjA8eY/bmcEpkmt hk4IVRE8FK7rMAwGA1UdEwQFMAMBAf8wCwYDVR0PBAQDAgH+MA0GCSqGSIb3DQEB CwUAA4IBAQBN2YpxKTt37zbIFsSkdexLX15Edh+RFw57lIar/uHZ4EgnAmOJ/8DP EE09zSml31v78CMtE6xgUOsKg41k27DAsnk3rlywyniOoYMhTiiuw49xAMQ/KaSX CJuaOOJAnCVXc7pKFFqkF1QF+Skw36hGJaackBY9dQhuCPuw2Tg8sIzOi7v94Nrw C7NZAa4Cr3gWFiYkzVgDhmhoUR2UqZdStwHu2b4Ksro2OMllpWXE3k4rZgow3eBE LG1zF85OOTypgX/cYElYCdZViRJJyPupcPsHViMNIbQ7IBKOENGZsCipV/UJZiZI 6inggEPaaPEtF/3X+QdksYP7Wg643zF7 -----END CERTIFICATE----- "

Chosen solution

you could enter about:config into the firefox address bar (confirm the info message in case it shows up) & search for the preference named security.enterprise_roots.enabled. double-click it and change its value to true and restart firefox once - this will import all custom certificates from the windows trust store into firefox and zscaler might become trusted this way. if this doesn't help either you'd have to get in contact with your it department to inquire how to properly set up the system to work with their network monitoring.

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All Replies (4)

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hi, is this happening in a corporate environment? according to your error details your connection is not a direct one to google.com but intercepted by a zscaler network appliance.

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Hi, yes - this is happening in a corporate environment. Is there a possibility to solve the problem?

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Chosen Solution

you could enter about:config into the firefox address bar (confirm the info message in case it shows up) & search for the preference named security.enterprise_roots.enabled. double-click it and change its value to true and restart firefox once - this will import all custom certificates from the windows trust store into firefox and zscaler might become trusted this way. if this doesn't help either you'd have to get in contact with your it department to inquire how to properly set up the system to work with their network monitoring.

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Thanks! This helped.