Sigma rule: Code Executed Via Office Add-in XLL File

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-5d700c7028f3, updated 2021-12-28T00:00:00.000Z.

Rule

Title: Code Executed Via Office Add-in XLL File
Status: test
Level: high
Author: frack113
Date: 2021-12-28
File: rules/windows/powershell/powershell_script/posh_ps_office_comobject_registerxll.yml
Commit: ccbb0369507f796db0b0ae6854c8a2be471b9d84

Adversaries may abuse Microsoft Office add-ins to obtain persistence on a compromised system.
Office add-ins can be used to add functionality to Office programs

Log source

product: windows
category: ps_script
definition: Requirements: Script Block Logging must be enabled

Detection

selection:
    ScriptBlockText|contains|all:
        - 'new-object '
        - '-ComObject '
        - '.application'
        - '.RegisterXLL'
condition: selection

False positives (as the rule lists them)

Unknown

MITRE ATT&CK ids this rule names

T1137.006

References

https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1137.006/T1137.006.md

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/powershell/powershell_script/posh_ps_office_comobject_registerxll.yml

Sources and licences

SigmaHQ
"Code Executed Via Office Add-in XLL File" by frack113 (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/powershell/powershell_script/posh_ps_office_comobject_registerxll.yml.
Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License
Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Code Executed Via Office Add-in XLL File",
entity page, dataset version ref-5d700c7028f3, updated 2021-12-28T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/36fbec91-fa1b-4d5d-8df1-8d8edcb632ad (accessed 2026-11-03).
Underlying source: SigmaHQ rule 36fbec91-fa1b-4d5d-8df1-8d8edcb632ad, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.