Extensions that are approved for use must be allowlisted.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-235755	EDGE-00-000042	SV-235755r766863_rule		Medium

Description
By default, all extensions are allowed. However, if all extensions are blocked by setting the "ExtensionInstallBlockList" policy to "*," users can only install extensions defined in this policy.

STIG	Date
Microsoft Edge Security Technical Implementation Guide	2021-11-19

Details

Check Text ( C-38974r766861_chk )
The policy value for "Computer Configuration/Administrative Templates/Microsoft Edge/Extensions/Allow specific extensions to be installed" must be set to "Enabled". Use the Windows Registry Editor to navigate to the following key: HKLM\SOFTWARE\Policies\Microsoft\Edge "ExtensionInstallAllowlist" must be set as follows: HKLM\SOFTWARE\Policies\Microsoft\Edge\ExtensionInstallAllowlist\1 = "extension_id1" HKLM\SOFTWARE\Policies\Microsoft\Edge\ExtensionInstallAllowlist\2 = "extension_id2" This requirement for "Allow specific extensions to be installed" is not required; this is optional. If configured, the list of extensions for which Microsoft Edge allows to be installed must be allowlisted; otherwise this is a finding.

Check Text ( C-38974r766861_chk )

The policy value for "Computer Configuration/Administrative Templates/Microsoft Edge/Extensions/Allow specific extensions to be installed" must be set to "Enabled".

Use the Windows Registry Editor to navigate to the following key:
HKLM\SOFTWARE\Policies\Microsoft\Edge

"ExtensionInstallAllowlist" must be set as follows:
HKLM\SOFTWARE\Policies\Microsoft\Edge\ExtensionInstallAllowlist\1 = "extension_id1"
HKLM\SOFTWARE\Policies\Microsoft\Edge\ExtensionInstallAllowlist\2 = "extension_id2"

This requirement for "Allow specific extensions to be installed" is not required; this is optional.

If configured, the list of extensions for which Microsoft Edge allows to be installed must be allowlisted; otherwise this is a finding.

Fix Text (F-38937r766862_fix)
Set the policy value for "Computer Configuration/Administrative Templates/Microsoft Edge/Extensions/Allow specific extensions to be installed" to "Enabled". A list of allowlisted extensions may then be specified.