Detection rules › Sigma
Office Macro File Creation
Detects the creation of a new office macro files on the systems
Known false positives
- Very common in environments that rely heavily on macro documents
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Initial Access |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 11: FileCreate |
Rule body
title: Office Macro File Creation
id: 91174a41-dc8f-401b-be89-7bfc140612a0
related:
- id: 0e29e3a7-1ad8-40aa-b691-9f82ecd33d66
type: similar
status: test
description: Detects the creation of a new office macro files on the systems
references:
- https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1566.001/T1566.001.md
- https://learn.microsoft.com/en-us/deployoffice/compat/office-file-format-reference
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-01-23
modified: 2026-01-09
tags:
- attack.initial-access
- attack.t1566.001
logsource:
category: file_event
product: windows
detection:
selection:
TargetFilename|endswith:
- '.docm'
- '.dotm'
- '.xlsm'
- '.xltm'
- '.potm'
- '.pptm'
filter_main_office:
Image|startswith:
- 'C:\Program Files\Microsoft Office\'
- 'C:\Program Files (x86)\Microsoft Office\'
Image|endswith:
- '\WINWORD.EXE'
- '\EXCEL.EXE'
- '\POWERPNT.EXE'
TargetFilename|contains: '\~$' # Temporary files created by Office applications
condition: selection and not 1 of filter_main_*
falsepositives:
- Very common in environments that rely heavily on macro documents
level: low
Stages and Predicates
Stage 0: condition
selection and not 1 of filter_main_*Stage 1: selection
selection:
TargetFilename|endswith:
- '.docm'
- '.dotm'
- '.xlsm'
- '.xltm'
- '.potm'
- '.pptm'
Stage 2: not filter_main_office
filter_main_office:
Image|startswith:
- 'C:\Program Files\Microsoft Office\'
- 'C:\Program Files (x86)\Microsoft Office\'
Image|endswith:
- '\WINWORD.EXE'
- '\EXCEL.EXE'
- '\POWERPNT.EXE'
TargetFilename|contains: '\~$'
Exclusions
The rule actively suppresses these predicates.
| Field | Kind | Excluded values | Search |
|---|---|---|---|
Image | ends_with | \EXCEL.EXE | excludes:Image field:"Image" value:"\EXCEL.EXE" |
Image | ends_with | \POWERPNT.EXE | excludes:Image field:"Image" value:"\POWERPNT.EXE" |
Image | ends_with | \WINWORD.EXE | excludes:Image field:"Image" value:"\WINWORD.EXE" |
Image | starts_with | C:\Program Files (x86)\Microsoft Office\ | excludes:Image field:"Image" value:"C:\Program Files (x86)\Microsoft Office\" |
Image | starts_with | C:\Program Files\Microsoft Office\ | excludes:Image field:"Image" value:"C:\Program Files\Microsoft Office\" |
TargetFilename | match | \~$ | excludes:TargetFilename field:"TargetFilename" value:"\~$" |
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
TargetFilename | ends_with |
| field:"TargetFilename" kind:ends_with |