How to Prevent ADFS Authentication Prompts in Firefox

Overview

This document describes how to prevent authentication prompts in Firefox web browser when accessing sites that use Microsoft Active Directory Federated Services (ADFS).

Symptoms

When going to a web site that uses Swinerton's ADFS for single sign-on using the Firefox web browser, there is a pop-up to enter the Swinerton username/password. This document describes how to configure Firefox so that authentication happens automatically and the pop-up does not appear, and the user does not need to enter their username and password.

Resolution Procedure

Add the URL of the Identity Provider (IdP) server as a trusted NTLM authentication source.

In the Firefox address bar, type about:config.
The browser will display a warning message, click Continue.
Search for network.automatic.
Double click on network.automatic-ntlm-auth.trusted-uris to modify the configuration.
Enter the IdP redirect address. For example https://adfs.example.com.
Click OK to exit the dialog box.

Reference

This is based on the article: https://www.cisco.com/c/en/us/support/docs/security/cloud-web-security/200560-Prevent-Repeated-Authentication-Prompts.html