Windows Registry TrustRecords Change for Macro-Enabled Documents in Suspicious Paths

Alert on Windows registry changes to Office TrustRecords where trusted-document paths fall in suspicious directories.

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windows-registry-trustrecords-change-for-macro-enabled-documents-in-suspicious-p-a166f74e

title: Windows Registry TrustRecords Change for Macro-Enabled Documents in Suspicious Paths
id: e4607f6f-54b0-4d7c-9e0b-bb6aabc12a72
related:
  - id: 295a59c1-7b79-4b47-a930-df12c15fc9c2
    type: derived
  - id: a166f74e-bf44-409d-b9ba-ea4b2dd8b3cd
    type: derived
status: test
description: This rule flags Windows registry modifications to Office trusted document trust records where the target path contains commonly suspicious locations. Attackers may abuse Office trust settings to persist and execute macro-enabled content while bypassing user security prompts. The detection relies on registry_set telemetry capturing changes to TargetObject values containing \Security\Trusted Documents\TrustRecords, and on matching the recorded path against specific cache/temp/public and similar locations.
references:
  - https://twitter.com/inversecos/status/1494174785621819397
  - Internal Research
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/registry/registry_set/registry_set_office_trust_record_susp_location.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2023-06-21
modified: 2023-08-17
tags:
  - attack.persistence
  - attack.defense-impairment
  - attack.t1112
logsource:
  category: registry_set
  product: windows
detection:
  selection_value:
    TargetObject|contains: \Security\Trusted Documents\TrustRecords
  selection_paths:
    TargetObject|contains:
      - /AppData/Local/Microsoft/Windows/INetCache/
      - /AppData/Local/Temp/
      - /PerfLogs/
      - C:/Users/Public/
      - file:///D:/
      - file:///E:/
  condition: all of selection_*
falsepositives:
  - Unlikely
level: high
license: DRL-1.1

What it detects

This rule flags Windows registry modifications to Office trusted document trust records where the target path contains commonly suspicious locations. Attackers may abuse Office trust settings to persist and execute macro-enabled content while bypassing user security prompts. The detection relies on registry_set telemetry capturing changes to TargetObject values containing \Security\Trusted Documents\TrustRecords, and on matching the recorded path against specific cache/temp/public and similar locations.

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.