TMA-OFFICE-2.2.4.7.2.4.1

Ensure 'Allow Trusted Locations on the network' is set to 'Disabled'

HighLevel 1Automatedoffice

Description

This policy setting controls whether trusted locations on the network can be used. Trusted locations specified in the Trust Center are used to define file locations that are assumed to be safe by the application opening the file. The recommended state for this setting is: Disabled. Rationale: Content, code, and add-ins are allowed to load from trusted locations with a minimal amount of security, without prompting the users for permission. User setting: the audit checks HKEY_USERS\<SID>\SOFTWARE\Policies\Microsoft\office\16.0\excel\security\trustedlocations:allownetworklocations (REG_DWORD) in every loaded user hive (S-1-5-21-*) and is compliant when each holds 0. It prints 'no-user-hive-loaded' (FAIL) when no user profile is loaded, so scan while users are logged on.

How it is checked

Audit method: Windows registry

registry

$sids = @(Get-ChildItem -Path 'Registry::HKEY_USERS' -ErrorAction SilentlyContinue | Where-Object { $_.PSChildName -match '^S-1-5-21-\d+-\d+-\d+-\d+$' } | ForEach-Object { $_.PSChildName }); if ($sids.Count -eq 0) { 'no-user-hive-loaded' } else { $bad = @(); foreach ($s in $sids) { $v = (Get-ItemProperty -Path ('Registry::HKEY_USERS\' + $s + '\SOFTWARE\Policies\Microsoft\office\16.0\excel\security\trustedlocations') -Name 'allownetworklocations' -ErrorAction SilentlyContinue).'allownetworklocations'; if (-not ($null -ne $v -and @(0) -contains [int64]$v)) { $bad += $s + ':allownetworklocations=' + $v } }; if ($bad.Count -eq 0) { 'compliant' } else { 'non-compliant: ' + ($bad -join ', ') } }

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Configure through Group Policy (User Configuration): User Configuration\Administrative Templates\Microsoft Excel 2016\Excel Options\Security\Trust Center\Trusted Locations\Allow Trusted Locations on the network = Disabled

Properties

Operating systems: Any
Tags: officeproductivitycis-l1
Reference: CIS Microsoft Office Enterprise Benchmark v2.0.0 - 2.2.4.7.2.4.1 Ensure 'Allow Trusted Locations on the network' is set to 'Disabled'

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target office