Outlook Macro Execution Without Warning Setting Enabled — Sigma Rule

Rule metadata and linked tags

Author: @ScoubiMtl. Source status: test; severity: high. Source dates: 2021-04-05 / 2023-08-17.

{
  "category": "registry_set",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 22e96ad56584806054518e3eca65c94f384d78970f91a78a2bc01c78a1a15fa7

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Outlook Macro Execution Without Warning Setting Enabled
id: e3b50fa5-3c3f-444e-937b-0a99d33731cd
status: test
description: Detects the modification of Outlook security setting to allow unprompted execution of macros.
references:
    - https://www.mdsec.co.uk/2020/11/a-fresh-outlook-on-mail-based-persistence/
    - https://speakerdeck.com/heirhabarov/hunting-for-persistence-via-microsoft-exchange-server-or-outlook?slide=53
author: '@ScoubiMtl'
date: 2021-04-05
modified: 2023-08-17
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.command-and-control
    - attack.t1137
    - attack.t1008
    - attack.t1546
logsource:
    category: registry_set
    product: windows
detection:
    selection:
        TargetObject|endswith: '\Outlook\Security\Level'
        Details|contains: '0x00000001' # Enable all Macros
    condition: selection
falsepositives:
    - Unlikely
level: high

Original YAML and metadata in JSON

False positives

• Unlikely

Source references

• https://www.mdsec.co.uk/2020/11/a-fresh-outlook-on-mail-based-persistence/
• https://speakerdeck.com/heirhabarov/hunting-for-persistence-via-microsoft-exchange-server-or-outlook?slide=53