Potential Persistence Via Excel Add-in - Registry — Sigma Rule

Rule metadata and linked tags

Author: frack113. Source status: test; severity: high. Source dates: 2023-01-15 / 2023-08-17.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 32ae724f1ef50ef0712aee42c7eab3ec1bb642acba9bfdf838dc5771bb992a20

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: Potential Persistence Via Excel Add-in - Registry
id: 961e33d1-4f86-4fcf-80ab-930a708b2f82
status: test
description: Detect potential persistence via the creation of an excel add-in (XLL) file to make it run automatically when Excel is started.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/4ae9580a1a8772db87a1b6cdb0d03e5af231e966/atomics/T1137.006/T1137.006.md
    - https://labs.withsecure.com/publications/add-in-opportunities-for-office-persistence
author: frack113
date: 2023-01-15
modified: 2023-08-17
tags:
    - attack.persistence
    - attack.t1137.006
logsource:
    product: windows
    category: registry_set
detection:
    selection:
        TargetObject|contains: 'Software\Microsoft\Office\'
        TargetObject|endswith: '\Excel\Options'
        Details|startswith: '/R '
        Details|endswith: '.xll'
    condition: selection
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://github.com/redcanaryco/atomic-red-team/blob/4ae9580a1a8772db87a1b6cdb0d03e5af231e966/atomics/T1137.006/T1137.006.md
• https://labs.withsecure.com/publications/add-in-opportunities-for-office-persistence