Kerberos authentication working for Chrome, Edge, Opera, and Brave, but not Firefox

Firefox (129.0.2) displays "401 - Unauthorized: Access is denied due to invalid credentials" (see attached image) I have tried various combinations of setting and not se… (funda kabanzi)

Firefox (129.0.2) displays "401 - Unauthorized: Access is denied due to invalid credentials" (see attached image)

I have tried various combinations of setting and not setting the following in Firefox:

  • network.negotiate-auth.trusted-uris
  • network.negotiate-auth.delegation-uris
  • network.auth.use-sspi

For the URI settings I have tried both .domainname.domainextension and https://servicename.domainname.domainextension

In Windows 10 Control Panel -> Internet Options, the site is in "Trusted sites" using a domain wildcard, and also "Local intranet" and both "Automatic logon" and "Enable Integrated Windows Authentication" are enabled. I suspect those setting aren't relevant since other browsers are authenticating without error or prompt, but calling this out to show that I've covered that base.

The web service is served by IIS 10.0 on Windows Server 2022 and the authentication provider list only includes Negotiate, but I don't believe this issue has anything to do with IIS or its configuration as, again, other browsers are authenticating without error or prompt.

Anything else to check?

Thank you for any guidance you can offer.

Asked by bryan 1 usuku oludlule