Firefox must not recommend extensions as the user is using the browser.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-251572	FFOX-00-000028	SV-251572r879587_rule		Medium

Description
The Recommended Extensions program recommends extensions to users as they surf the web. The user must not be encouraged to install extensions from the websites they visit. Allowed extensions are to be centrally managed.

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

Details

Check Text ( C-55007r807186_chk )
Type "about:policies" in the browser address bar. If "UserMessaging" is not displayed under Policy Name or the Policy Value is not "ExtensionRecommendations" with a value of "false", this is a finding.

Fix Text (F-54961r807187_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\User Messaging Policy Name: Extension Recommendations Policy State: Disabled macOS "plist" file: Add the following: UserMessaging ExtensionRecommendations Linux "policies.json" file: Add the following in the policies section: "UserMessaging": { "ExtensionRecommendations": false }

Fix Text (F-54961r807187_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\User Messaging
Policy Name: Extension Recommendations
Policy State: Disabled

macOS "plist" file:
Add the following:
UserMessaging

ExtensionRecommendations

Linux "policies.json" file:
Add the following in the policies section:
"UserMessaging": {
"ExtensionRecommendations": false
}