Detection rules › Splunk

Windows Excel Spawning Microsoft Project Application

Status
production
Severity
low
Group by
IntegrityLevel, command_line, computer_name, event_action, original_file_name, parent_command_line, parent_process_guid, parent_process_id, parent_process_name, process_guid, process_hash, process_id, process_name, user, user_id, vendor_product
Author
Teoderick Contreras, Splunk
Source
github.com/splunk/security_content

The following analytic identifies the execution of uncommon Microsoft application executables as child processes of Microsoft Excel. Under normal conditions, Excel primarily spawns internal Office-related processes, and the creation of executables such as WINPROJ.EXE, FOXPROW.exe, or SCHDPLUS.exe is uncommon in typical business workflows. Adversaries may abuse this behavior to blend malicious activity within trusted applications, execute unauthorized code, or bypass application control mechanisms. This technique aligns with common tradecraft where Office applications are leveraged as initial access or execution vectors due to their prevalence in enterprise environments. Detecting this relationship helps defenders spot suspicious child processes that may indicate malware execution, persistence mechanisms, or attempts to establish command-and-control. Security teams should investigate the parent Excel process, the context of the ActivateMicrosoftApp() execution, and any subsequent network or file activity. While certain legitimate Office features could trigger this process in specific environments, its occurrence generally warrants further scrutiny to validate intent and rule out compromise.

MITRE ATT&CK coverage

Event coverage

Rule body splunk

name: Windows Excel Spawning Microsoft Project Application
id: ee54241e-0815-4423-9729-e1f5dfc402de
version: 3
creation_date: '2025-08-21'
modification_date: '2026-05-13'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: |
    The following analytic identifies the execution of uncommon Microsoft application executables as child processes of Microsoft Excel.
    Under normal conditions, Excel primarily spawns internal Office-related processes, and the creation of executables such as WINPROJ.EXE, FOXPROW.exe, or SCHDPLUS.exe is uncommon in typical business workflows.
    Adversaries may abuse this behavior to blend malicious activity within trusted applications, execute unauthorized code, or bypass application control mechanisms.
    This technique aligns with common tradecraft where Office applications are leveraged as initial access or execution vectors due to their prevalence in enterprise environments.
    Detecting this relationship helps defenders spot suspicious child processes that may indicate malware execution, persistence mechanisms, or attempts to establish command-and-control.
    Security teams should investigate the parent Excel process, the context of the ActivateMicrosoftApp() execution, and any subsequent network or file activity.
    While certain legitimate Office features could trigger this process in specific environments, its occurrence generally warrants further scrutiny to validate intent and rule out compromise.
data_source:
    - Sysmon EventID 1
    - Windows Event Log Security 4688
    - CrowdStrike ProcessRollup2
search: |-
    | tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime
    FROM datamodel=Endpoint.Processes WHERE
    Processes.parent_process_name = "EXCEL.EXE"
    Processes.process_name IN ("WINPROJ.EXE", "FOXPROW.exe","SCHDPLUS.exe")
      BY Processes.action Processes.dest Processes.original_file_name
         Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
         Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
         Processes.process Processes.process_exec Processes.process_guid
         Processes.process_hash Processes.process_id Processes.process_integrity_level
         Processes.process_name Processes.process_path Processes.user
         Processes.user_id Processes.vendor_product
    | `drop_dm_object_name(Processes)`
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `windows_excel_spawning_microsoft_project_application_filter`
how_to_implement: |
    The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint` data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.
known_false_positives: |
    Microsoft Project has been discontinued since January 2010, so its presence is unlikely in modern environments.
    If a related child process is observed, verify its legitimacy to rule out potential misuse.
references:
    - https://specterops.io/blog/2023/10/30/lateral-movement-abuse-the-power-of-dcom-excel-application/
    - https://blog.talosintelligence.com/pathwiper-targets-ukraine/
    - https://www.trellix.com/blogs/research/dcom-abuse-and-network-erasure-with-trellix-ndr/
drilldown_searches:
    - name: View the detection results for - "$dest$" and "$user$"
      search: '%original_detection_search% | search  dest = "$dest$" user = "$user$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$dest$" and "$user$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$", "$user$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: 7d
      latest_offset: "0"
intermediate_findings:
    entities:
        - field: dest
          type: system
          score: 20
          message: $parent_process_name$ spawned $process_name$ on $dest$, indicative of ActivateMicrosoftApp() use
threat_objects:
    - field: parent_process_name
      type: parent_process_name
    - field: process
      type: process
analytic_story:
    - PathWiper
asset_type: Endpoint
mitre_attack_id:
    - T1021.003
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1021.003/excel_activemicrosoftapp/sysmon_winprojexe.log
          source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
          sourcetype: XmlWinEventLog
      test_type: unit

Stages and Predicates

Stage 1: tstats

| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime
FROM datamodel=Endpoint.Processes WHERE
Processes.parent_process_name = "EXCEL.EXE"
Processes.process_name IN ("WINPROJ.EXE", "FOXPROW.exe","SCHDPLUS.exe")
  BY Processes.action Processes.dest Processes.original_file_name
     Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
     Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
     Processes.process Processes.process_exec Processes.process_guid
     Processes.process_hash Processes.process_id Processes.process_integrity_level
     Processes.process_name Processes.process_path Processes.user
     Processes.user_id Processes.vendor_product

Stage 2: search

| `drop_dm_object_name(Processes)`

Stage 3: search

| `security_content_ctime(firstTime)`

Stage 4: search

| `security_content_ctime(lastTime)`

Stage 5: search

| `windows_excel_spawning_microsoft_project_application_filter`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
Processes.parent_process_nameeq
  • "EXCEL.EXE"
Processes.process_namein
  • "FOXPROW.exe"
  • "SCHDPLUS.exe"
  • "WINPROJ.EXE"