Ensure 'Always prevent untrusted Microsoft Query files from opening' is set to 'Enabled'

HighLevel 1Automatedoffice

Description

This policy setting controls whether Microsoft Query files (.iqy, oqy, .dqy, and .rqy) in an untrusted location are prevented from opening. Using Microsoft Query, users can connect to external data sources, select data from those external sources, import that data into worksheets, and refresh it to keep worksheet data synchronized with the data in the external sources. Rationale: Microsoft Query files that have been tampered with and placed in an untrusted location could allow an attacker to affect the confidentiality and integrity of a spreadsheet. User setting: the audit checks HKEY_USERS\<SID>\SOFTWARE\Policies\Microsoft\office\16.0\excel\security\externalcontent:enableblockunsecurequeryfiles (REG_DWORD) in every loaded user hive (S-1-5-21-*) and is compliant when each holds 1. 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\' + $s + '\SOFTWARE\Policies\Microsoft\office\16.0\excel\security\externalcontent') -Name 'enableblockunsecurequeryfiles' -ErrorAction SilentlyContinue).'enableblockunsecurequeryfiles'; if (-not ($null -ne $v -and @(1) -contains [int64]$v)) { $bad += $s + ':enableblockunsecurequeryfiles=' + $v } }; if ($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\External Content\Always prevent untrusted Microsoft Query files from opening = Enabled

Properties

Operating systems: Any
Tags: officeproductivitycis-l1
Reference: CIS Microsoft Office Enterprise Benchmark v2.0.0 - 2.2.4.7.2.1.1 Ensure 'Always prevent untrusted Microsoft Query files from opening' is set to 'Enabled'

Check this host

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

shell

tmaegis scan --target office