Microsoft VBA For Outlook Addin Loaded Via Outlook — Sigma Rule

Rule metadata and linked tags

Author: Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: medium. Source dates: 2023-02-08 / 2024-03-12.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 2ee5f7ce4487e6ccdecd3a7e1a8dd7ddb8aa840f56da0b1d0caf093f84364ceb

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: Microsoft VBA For Outlook Addin Loaded Via Outlook
id: 9a0b8719-cd3c-4f0a-90de-765a4cb3f5ed
status: test
description: Detects outlvba (Microsoft VBA for Outlook Addin) DLL being loaded by the outlook process
references:
    - https://speakerdeck.com/heirhabarov/hunting-for-persistence-via-microsoft-exchange-server-or-outlook?slide=58
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-02-08
modified: 2024-03-12
tags:
    - attack.execution
    - attack.t1204.002
logsource:
    category: image_load
    product: windows
detection:
    selection:
        Image|endswith: '\outlook.exe'
        ImageLoaded|endswith: '\outlvba.dll'
    condition: selection
falsepositives:
    - Legitimate macro usage. Add the appropriate filter according to your environment
level: medium

Original YAML and metadata in JSON

False positives

• Legitimate macro usage. Add the appropriate filter according to your environment

Source references

• https://speakerdeck.com/heirhabarov/hunting-for-persistence-via-microsoft-exchange-server-or-outlook?slide=58