Child Processes of Spoolsv exe

name: Child Processes of Spoolsv exe
id: aa0c4aeb-5b18-41c4-8c07-f1442d7599df
version: 10
date: '2026-03-10'
author: Rico Valdez, Splunk
status: experimental
type: TTP
description: The following analytic identifies child processes spawned by spoolsv.exe, the Print Spooler service in Windows, which typically runs with SYSTEM privileges. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process and parent process relationships. Monitoring this activity is crucial as it can indicate exploitation attempts, such as those associated with CVE-2018-8440, which can lead to privilege escalation. If confirmed malicious, attackers could gain SYSTEM-level access, allowing them to execute arbitrary code, escalate privileges, and potentially compromise the entire system.
data_source:
    - Sysmon EventID 1
    - Windows Event Log Security 4688
    - CrowdStrike ProcessRollup2
search: |-
    | tstats `security_content_summariesonly` count values(Processes.process_name) as process_name values(Processes.process) as process min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes
      WHERE Processes.parent_process_name=spoolsv.exe
        AND
        Processes.process_name!=regsvr32.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)`
    | `child_processes_of_spoolsv_exe_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: Some legitimate printer-related processes may show up as children of spoolsv.exe. You should confirm that any activity as legitimate and may be added as exclusions in the search.
references: []
rba:
    message: Potentially suspicious child processes of spoolsv.exe on $dest$
    risk_objects:
        - field: user
          type: user
          score: 50
        - field: dest
          type: system
          score: 50
    threat_objects: []
tags:
    analytic_story:
        - Data Destruction
        - Hermetic Wiper
        - Windows Privilege Escalation
    asset_type: Endpoint
    cve:
        - CVE-2018-8440
    mitre_attack_id:
        - T1068
    product:
        - Splunk Enterprise
        - Splunk Enterprise Security
        - Splunk Cloud
    security_domain: endpoint