Windows Suspicious EXE in User Directory Launched by Microsoft Office Applications

Alert on Office spawning a .exe from C:\users\ (except when the child is Teams.exe).

FreeReviewedSigma · High · v1

Product: windows
Category: process_creation
Author: Jason Lynch (SigmaHQ), DRL 1.1
Published: 2019-04-02
Updated: 2026-07-30

ATT&CK techniques

Execution

Recon
Resource Dev
Initial Access
Execution
- T1204.002Malicious File
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule flags process executions where an Office application (Word, Excel, PowerPoint, Publisher, Visio, Access, or Equation Editor) starts an executable located under the user directory (C:\users\) that ends with .exe. Such behavior matters because it can indicate user-writable execution paths used to run malware or unauthorized payloads from Office-launched processes. It relies on Windows process creation telemetry, specifically the parent process image and the child process image path.

Reporting behind it

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Windows Suspicious EXE in User Directory Launched by Microsoft Office Applications

Pivot detection · T1204.002 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

windows-suspicious-exe-in-user-directory-launched-by-microsoft-office-applicatio-aa3a6f94

title: Windows Suspicious EXE in User Directory Launched by Microsoft Office Applications
id: ca269059-28e7-452a-a411-cf92308eff22
status: test
description: This rule flags process executions where an Office application (Word, Excel, PowerPoint, Publisher, Visio, Access, or Equation Editor) starts an executable located under the user directory (C:\users\) that ends with .exe. Such behavior matters because it can indicate user-writable execution paths used to run malware or unauthorized payloads from Office-launched processes. It relies on Windows process creation telemetry, specifically the parent process image and the child process image path.
references:
  - https://blog.morphisec.com/fin7-not-finished-morphisec-spots-new-campaign
  - https://www.virustotal.com/gui/file/23160972c6ae07f740800fa28e421a81d7c0ca5d5cab95bc082b4a986fbac57
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_office_spawn_exe_from_users_directory.yml
author: Jason Lynch, Huntrule Team
date: 2019-04-02
modified: 2023-02-04
tags:
  - attack.execution
  - attack.t1204.002
  - attack.g0046
  - car.2013-05-002
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    ParentImage|endswith:
      - \WINWORD.EXE
      - \EXCEL.EXE
      - \POWERPNT.exe
      - \MSPUB.exe
      - \VISIO.exe
      - \MSACCESS.exe
      - \EQNEDT32.exe
    Image|startswith: C:\users\
    Image|endswith: .exe
  filter:
    Image|endswith: \Teams.exe
  condition: selection and not filter
falsepositives:
  - Unknown
level: high
license: DRL-1.1
related:
  - id: aa3a6f94-890e-4e22-b634-ffdfd54792cc
    type: derived

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