## Guide to the Secure Configuration of Firefox

The SCAP Security Guide Project
https://www.open-scap.org/security-policies/scap-security-guide
This guide presents a catalog of security-relevant configuration settings for Firefox. It is a rendering of content structured in the eXtensible Configuration Checklist Description Format (XCCDF) in order to support security automation. The SCAP content is is available in the `scap-security-guide` package which is developed at https://www.open-scap.org/security-policies/scap-security-guide.
Providing system administrators with such guidance informs them how to securely configure systems under their control in a variety of network roles. Policy makers and baseline creators can use this catalog of settings, with its associated references to higher-level security control catalogs, in order to assist them in security baseline creation. This guide is a catalog, not a checklist, and satisfaction of every item is not likely to be possible or sensible in many operational scenarios. However, the XCCDF format enables granular selection and adjustment of settings, and their association with OVAL and OCIL content provides an automated checking capability. Transformations of this document, and its associated automated checking content, are capable of providing baselines that meet a diverse set of policy objectives. Some example XCCDF Profiles, which are selections of items that form checklists and can be used as baselines, are available with this guide. They can be processed, in an automated fashion, with tools that support the Security Content Automation Protocol (SCAP). The DISA STIG for Firefox, which provides required settings for US Department of Defense systems, is one example of a baseline created from this guidance.
Do not attempt to implement any of the settings in this guide without first testing them in a non-operational environment. The creators of this guidance assume no responsibility whatsoever for its use by other parties, and makes no guarantees, expressed or implied, about its quality, reliability, or any other characteristic.

Profile ID | (default)

## Revision History

Current version: 0.1.31

- draft (as of 2017-08-11)

## Platforms

- cpe:/a:mozilla:firefox

## Table of Contents

1. Remediation functions used by the SCAP Security Guide Project
2. Introduction

1. How to Use This Guide

3. Firefox

1. Prevent Users from Changing Firefox Configuration Settings
2. The DoD Root Certificate Is Required
3. Clearing Cookies And Other Data

## Checklist

### Remediation functions used by the SCAP Security Guide Project [ref]group

XCCDF form of the various remediation functions as used by remediation scripts from the SCAP Security Guide Project

### Introduction [ref]group

The purpose of this guidance is to provide security configuration recommendations and baselines for the Firefox application. Recommended settings for the basic application are provided. The guide is intended for system administrators. Readers are assumed to possess basic system administration skills for Unix-like systems, as well as some familiarity with the product's documentation and administration conventions. Some instructions within this guide are complex. All directions should be followed completely and with understanding of their effects in order to avoid serious adverse effects on the system and its security.

### How to Use This Guide [ref]group

Readers should heed the following points when using the guide.

### Read Sections Completely and in Order [ref]group

Each section may build on information and recommendations discussed in prior sections. Each section should be read and understood completely; instructions should never be blindly applied. Relevant discussion may occur after instructions for an action.

### Test in Non-Production Environment [ref]group

This guidance should always be tested in a non-production environment before deployment. This test environment should simulate the setup in which the system will be deployed as closely as possible.

### Root Shell Environment Assumed [ref]group

Most of the actions listed in this document are written with the assumption that they will be executed by the root user running the `/bin/bash` shell. Commands preceded with a hash mark (#) assume that the administrator will execute the commands as root, i.e. apply the command via `sudo` whenever possible, or use `su` to gain root privileges if `sudo` cannot be used. Commands which can be executed as a non-root user are are preceded by a dollar sign ($) prompt.

### Formatting Conventions [ref]group

Commands intended for shell execution, as well as configuration file text, are featured in a `monospace font`. Italics are used to indicate instances where the system administrator must substitute the appropriate information into a command or configuration file.

### Firefox [ref]group

Firefox is an open-source web browser and developed by Mozilla. Web browsers such as Firefox are used for a number of reasons. This section provides settings for configuring Firefox policies to meet compliance settings for Firefox running on Red Hat Enterprise Linux systems.

Refer to
- http://kb.mozillazine.org/Firefox_:_FAQs_:_About:config_Entries
for a list of currently supported Firefox settings.

### Prevent Users from Changing Firefox Configuration Settings [ref]group

Firefox required security preferences cannot be changed by users.

References: ECSC-1, http://iase.disa.mil/stigs/cci/Pages/index.aspx

### The DoD Root Certificate Is Required [ref]group

The Shared System Certificates store contains certificates that applications can access for a single certificate repository. If enabled, Firefox can access that single system certificate repository. If the DoD root certificate is also installed into the shared system certificate repository, Firefox will see and use the DoD root certificate as a valid certificate authority.

References: AC-10, 54

### Clearing Cookies And Other Data [ref]group

Browser preferences should be set to perform a Clear Private Data operation when closing the browser in order to clear cookies and other data installed by websites visited during the session.

References: ECSC-1, http://iase.disa.mil/stigs/cci/Pages/index.aspx

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