Windows Registry: Microsoft Office Protected View Disabled via Security Policy Keys

Flags Windows registry updates that disable Microsoft Office Protected View for attachments, internet files, UNC paths, or unsafe locations.

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windows-registry-microsoft-office-protected-view-disabled-via-security-policy-ke-a5c7a43f

title: "Windows Registry: Microsoft Office Protected View Disabled via Security Policy Keys"
id: b0bb5d75-9b5b-4229-ab22-7f7d3b0ba4b4
related:
  - id: 7c637634-c95d-4bbf-b26c-a82510874b34
    type: obsolete
  - id: a5c7a43f-6009-4a8c-80c5-32abf1c53ecc
    type: derived
status: test
description: This rule identifies registry changes under Microsoft Office Protected View policy paths where values indicate Protected View is disabled for specific content or locations. Disabling Protected View reduces safety checks on files opened from untrusted sources, which can help attackers increase the impact of malicious documents. It relies on Windows registry set telemetry matching the targeted Office ProtectedView key path and specific DWORD value settings.
references:
  - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1562.001/T1562.001.md
  - https://unit42.paloaltonetworks.com/unit42-gorgon-group-slithering-nation-state-cybercrime/
  - https://yoroi.company/research/cyber-criminal-espionage-operation-insists-on-italian-manufacturing/
  - https://admx.help/HKCU/software/policies/microsoft/office/16.0/excel/security/protectedview
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/registry/registry_set/registry_set_office_disable_protected_view_features.yml
author: frack113, Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2021-06-08
modified: 2023-08-17
tags:
  - attack.defense-impairment
  - attack.t1685
logsource:
  product: windows
  category: registry_set
detection:
  selection_path:
    TargetObject|contains|all:
      - \SOFTWARE\Microsoft\Office\
      - \Security\ProtectedView\
  selection_values_1:
    Details: DWORD (0x00000001)
    TargetObject|endswith:
      - \DisableAttachementsInPV
      - \DisableInternetFilesInPV
      - \DisableIntranetCheck
      - \DisableUnsafeLocationsInPV
  selection_values_0:
    Details: DWORD (0x00000000)
    TargetObject|endswith:
      - \enabledatabasefileprotectedview
      - \enableforeigntextfileprotectedview
  condition: selection_path and 1 of selection_values_*
falsepositives:
  - Unlikely
level: high
license: DRL-1.1

What it detects

This rule identifies registry changes under Microsoft Office Protected View policy paths where values indicate Protected View is disabled for specific content or locations. Disabling Protected View reduces safety checks on files opened from untrusted sources, which can help attackers increase the impact of malicious documents. It relies on Windows registry set telemetry matching the targeted Office ProtectedView key path and specific DWORD value settings.

Known false positives

Unlikely

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.