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Can't prevent Firefox from blocking a https site whose certificate has not been identified

  • 6 replies
  • 1 has this problem
  • 1 view
  • Last reply by galoget

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I am trying to connect to an https URL that has issued a certificate that is not valid, for the issuer is unknown: https://www.sede.fnmt.gob.es/certificados/persona-fisica/obtener-certificado-software/solicitar-certificado

I am aware of this and I accept the risk and want to proceed. I have added the URL as an Exception in the Security tab under Preferences but Firefox kept blocking me. I have then erased all navigation history, cookies, etc. and ticked off all blocking options under the same Security tab, with the same result.

Could you please advice?

Many thanks

I am trying to connect to an https URL that has issued a certificate that is not valid, for the issuer is unknown: https://www.sede.fnmt.gob.es/certificados/persona-fisica/obtener-certificado-software/solicitar-certificado I am aware of this and I accept the risk and want to proceed. I have added the URL as an Exception in the Security tab under Preferences but Firefox kept blocking me. I have then erased all navigation history, cookies, etc. and ticked off all blocking options under the same Security tab, with the same result. Could you please advice? Many thanks
Attached screenshots

Chosen solution

Hi rodder,

Mmmm, that error is strange, but try the following steps:

  1. Copy the address that is causing the problem (e.g. https://apus20.cert.fnmt.es)
  2. In your Firefox browser, go to Preferences -> Advanced -> Certificates, View Certificates.
  3. On "Servers" tab, press Add Exception
  4. Then paste the address (e.g. https://apus20.cert.fnmt.es) and press "Get Certificate"
  5. Afther that, Confirm Security Exception, it worked for me, and is not asking again to trust this site.

Tell me if it works for you in this way, also here is the screenshot of the process.

Cheers,

Galoget Líder de la Comunidad de Software Libre y Seguridad Informática Hackem OWASP Ecuador Student Chapter Leader Mozillian & FSA Fedora Ambassador for Ecuador OpenStreetMap Ecuador Leader

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All Replies (6)

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Hello rodder73,

You can use this add-on to skip that error message: https://addons.mozilla.org/en-US/firefox/addon/skip-cert-error/

"This Firefox extension enables skipping the SSL/TLS certificate error page, for specific configurable conditions, like self-signed cert or unknown issuer, by adding a temporary exception."

Hope you find it useful.

Cheers!

Galoget Líder de la Comunidad de Software Libre y Seguridad Informática Hackem OWASP Ecuador Student Chapter Leader Mozillian & FSA Fedora Ambassador for Ecuador OpenStreetMap Ecuador Leader

==========

Hola rodder73,

Para evitar que se te muestre la pantalla de advertencia de Mozilla Firefox para certificados desconocidos, puedes utilizar el complemento "Skip Cert Error", lo puedes descargar desde aquí: https://addons.mozilla.org/en-US/firefox/addon/skip-cert-error/

Te adjunto su descripción: "This Firefox extension enables skipping the SSL/TLS certificate error page, for specific configurable conditions, like self-signed cert or unknown issuer, by adding a temporary exception."

Espero que te sirva.

Saludos!

Galoget Líder de la Comunidad de Software Libre y Seguridad Informática Hackem OWASP Ecuador Student Chapter Leader Mozillian & FSA Fedora Ambassador for Ecuador OpenStreetMap Ecuador Leader

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galoget said

Hello rodder73, You can use this add-on to skip that error message: https://addons.mozilla.org/en-US/firefox/addon/skip-cert-error/ "This Firefox extension enables skipping the SSL/TLS certificate error page, for specific configurable conditions, like self-signed cert or unknown issuer, by adding a temporary exception." Hope you find it useful. Cheers! Galoget Líder de la Comunidad de Software Libre y Seguridad Informática Hackem OWASP Ecuador Student Chapter Leader Mozillian & FSA Fedora Ambassador for Ecuador OpenStreetMap Ecuador Leader
==========

Hola rodder73,

Para evitar que se te muestre la pantalla de advertencia de Mozilla Firefox para certificados desconocidos, puedes utilizar el complemento "Skip Cert Error", lo puedes descargar desde aquí: https://addons.mozilla.org/en-US/firefox/addon/skip-cert-error/

Te adjunto su descripción: "This Firefox extension enables skipping the SSL/TLS certificate error page, for specific configurable conditions, like self-signed cert or unknown issuer, by adding a temporary exception."

Espero que te sirva.

Saludos!

Galoget Líder de la Comunidad de Software Libre y Seguridad Informática Hackem OWASP Ecuador Student Chapter Leader Mozillian & FSA Fedora Ambassador for Ecuador OpenStreetMap Ecuador Leader

Hi Galoget,

Many thanks for your quick response. I have installed the plugin and tried again, but unfortunately it keeps yielding the same error message:

"apus20.cert.fnmt.es usa un certificado de seguridad no válido. No se confía en el certificado porque el certificado emisor es desconocido. (Código de error: sec_error_unknown_issuer)"

Based on the plug-in information, this unknkown issuer error should be skipped but somehow it does not work.

Any ideas of what could I be doing wrong?

Thanks in advance

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Chosen Solution

Hi rodder,

Mmmm, that error is strange, but try the following steps:

  1. Copy the address that is causing the problem (e.g. https://apus20.cert.fnmt.es)
  2. In your Firefox browser, go to Preferences -> Advanced -> Certificates, View Certificates.
  3. On "Servers" tab, press Add Exception
  4. Then paste the address (e.g. https://apus20.cert.fnmt.es) and press "Get Certificate"
  5. Afther that, Confirm Security Exception, it worked for me, and is not asking again to trust this site.

Tell me if it works for you in this way, also here is the screenshot of the process.

Cheers,

Galoget Líder de la Comunidad de Software Libre y Seguridad Informática Hackem OWASP Ecuador Student Chapter Leader Mozillian & FSA Fedora Ambassador for Ecuador OpenStreetMap Ecuador Leader

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You were right galoget, it did work this time :-)

Many thanks for your responsiveness and the great help you provided.

Rodder

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Hi!

Glad your problem is resolved. If you have not done yet, I ask you to select the answer that solves your problem, So give other users who have similar problems to find the solution more quickly.

Thank you for to contact Help Mozilla.

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Hi rodder73,

Thanks for your confirmation, I am happy that your problem is solved, and as Tailer says, please do not forget to select the answer to your problem.

Cheers,

Galoget Líder de la Comunidad de Software Libre y Seguridad Informática Hackem OWASP Ecuador Student Chapter Leader Mozillian & FSA Fedora Ambassador for Ecuador OpenStreetMap Ecuador Leader