Jscript Execution Using Cscript App

name: Jscript Execution Using Cscript App
id: 002f1e24-146e-11ec-a470-acde48001122
version: 15
creation_date: '2021-09-14'
modification_date: '2026-10-09'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: |-
    The following analytic detects the execution of JScript using the cscript.exe process.
    It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process and command-line telemetry.
    This behavior is significant because JScript files are typically executed by wscript.exe, making cscript.exe execution unusual and potentially indicative of malicious activity, such as the FIN7 group's tactics.
    If confirmed malicious, this activity could allow attackers to execute arbitrary scripts, leading to code execution, data exfiltration, or further system compromise.
data_source:
    - Sysmon EventID 1
search: |-
    | tstats `security_content_summariesonly`
      count min(_time) as firstTime
            max(_time) as lastTime

    FROM datamodel=Endpoint.Processes WHERE
    (
        (
            Processes.parent_process_name = "cscript.exe"
            Processes.parent_process = "*//e:jscript*"
        )
        OR
        (
            Processes.process_name = "cscript.exe"
            Processes.process = "*//e:jscript*"
        )
    )

    NOT Processes.process="*/Job:AgentHIScript*"
    NOT Processes.parent_process="*/Job:AgentHIScript*"

    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)`
    | `jscript_execution_using_cscript_app_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: |-
    Symantec Host Integrity check uses Jscript through cscript.exe
references:
    - https://www.mandiant.com/resources/fin7-pursuing-an-enigmatic-and-evasive-global-criminal-operation
    - https://attack.mitre.org/groups/G0046/
    - https://nasbench.medium.com/symantec-endpoint-protection-meets-com-using-symantec-sshelper-as-a-lolbin-40d515a121ce
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: The process [$parent_process_name$] with commandline [$parent_process$] launched [$process_name$] with commandline [$process$] on [$dest$]
threat_objects:
    - field: parent_process
      type: process
    - field: process
      type: process
analytic_story:
    - FIN7
    - Remcos
asset_type: Endpoint
mitre_attack_id:
    - T1059.007
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/malware/fin7/fin7_macro_js_1/sysmon.log
          source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
          sourcetype: XmlWinEventLog
      test_type: unit