The Firefox New Tab page must not show Top Sites, Sponsored Top Sites, Pocket Recommendations, Sponsored Pocket Stories, Searches, Highlights, or Snippets.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-251573	FFOX-00-000029	SV-251573r879587_rule		Medium

Description
The New Tab page by default shows a list of built-in top sites, as well as the top sites the user has visited. It is detrimental for applications to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities or services are often overlooked and therefore may remain unsecured. They increase the risk to the platform by providing additional attack vectors. Applications are capable of providing a wide variety of functions and services. Some of the functions and services, provided by default, may not be necessary to support essential organizational operations (e.g., key missions, functions). Examples of non-essential capabilities include but are not limited to advertising software or browser plug-ins that are not related to requirements or provide a wide array of functionality not required for every mission but that cannot be disabled. The new tab page must not actively show user activity.

Description

The New Tab page by default shows a list of built-in top sites, as well as the top sites the user has visited. It is detrimental for applications to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities or services are often overlooked and therefore may remain unsecured. They increase the risk to the platform by providing additional attack vectors. Applications are capable of providing a wide variety of functions and services. Some of the functions and services, provided by default, may not be necessary to support essential organizational operations (e.g., key missions, functions). Examples of non-essential capabilities include but are not limited to advertising software or browser plug-ins that are not related to requirements or provide a wide array of functionality not required for every mission but that cannot be disabled. The new tab page must not actively show user activity.

STIG	Date
Mozilla Firefox Security Technical Implementation Guide	2023-06-05

Details

Check Text ( C-55008r822779_chk )
Type "about:policies" in the browser address bar. If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "Search" with a value of "false", this is a finding. If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "TopSites" with a value of "false", this is a finding. If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "SponsoredTopSites" with a value of "false", this is a finding. If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "Pocket" with a value of "false", this is a finding. If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "SponsoredPocket" with a value of "false", this is a finding. If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "Highlights" with a value of "false", this is a finding. If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "Snippets" with a value of "false", this is a finding. If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "Locked" with a value of "true", this is a finding.

Check Text ( C-55008r822779_chk )

Type "about:policies" in the browser address bar.

If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "Search" with a value of "false", this is a finding.
If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "TopSites" with a value of "false", this is a finding.
If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "SponsoredTopSites" with a value of "false", this is a finding.
If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "Pocket" with a value of "false", this is a finding.
If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "SponsoredPocket" with a value of "false", this is a finding.
If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "Highlights" with a value of "false", this is a finding.
If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "Snippets" with a value of "false", this is a finding.
If "FirefoxHome" is not displayed under Policy Name or the Policy Value does not have "Locked" with a value of "true", this is a finding.

Fix Text (F-54962r822780_fix)
Windows group policy: 1. Open the group policy editor tool with "gpedit.msc". 2. Navigate to Policy Path: Computer Configuration\Administrative Templates\Mozilla\Firefox Policy Name: Customize Firefox Home Policy State: Enabled Policy Value: Uncheck "Search" Policy Value: Uncheck "Top Sites" Policy Value: Uncheck "Sponsored Top Sites" Policy Value: Uncheck "Recommended by Pocket" Policy Value: Uncheck "Sponsored Pocket Stories" Policy Value: Uncheck "Download History" Policy Value: Uncheck "Snippets" Policy Value: Check "Do not allow settings to be changed" macOS "plist" file: Add the following: FirefoxHome Search TopSites SponsoredTopSites Pocket SponsoredPocket Highlights Snippets Locked Linux "policies.json" file: Add the following in the policies section: "FirefoxHome": { "Search": false, "TopSites": false, "SponsoredTopSites": false, "Pocket": false, "SponsoredPocket": false, "Highlights": false, "Snippets": false, "locked": true }

Fix Text (F-54962r822780_fix)

Windows group policy:
1. Open the group policy editor tool with "gpedit.msc".
2. Navigate to Policy Path: Computer Configuration\Administrative Templates\Mozilla\Firefox
Policy Name: Customize Firefox Home
Policy State: Enabled
Policy Value: Uncheck "Search"
Policy Value: Uncheck "Top Sites"
Policy Value: Uncheck "Sponsored Top Sites"
Policy Value: Uncheck "Recommended by Pocket"
Policy Value: Uncheck "Sponsored Pocket Stories"
Policy Value: Uncheck "Download History"
Policy Value: Uncheck "Snippets"
Policy Value: Check "Do not allow settings to be changed"

macOS "plist" file:
Add the following:
FirefoxHome

Search

TopSites

SponsoredTopSites

Pocket

SponsoredPocket

Highlights

Snippets

Locked

Linux "policies.json" file:
Add the following in the policies section:
"FirefoxHome": {
"Search": false,
"TopSites": false,
"SponsoredTopSites": false,
"Pocket": false,
"SponsoredPocket": false,
"Highlights": false,
"Snippets": false,
"locked": true
}