Powershell Defender Threat Actions Set to Allow

SPLUNK detection rule by Teoderick Contreras, Splunk · Apache-2.0

The following analytic detects the setting of the Windows Defender Threat Actions to allow. It leverages data from the Endpoint.Processes data model, specifically monitoring the execution of the `Set-MpPreference` cmdlet with the `-HighThreatDefaultAction`, `-ModerateThreatDefaultAction`, `-LowThreatDefaultAction`, and `-SevereThreatDefaultAction` parameters set to `6`. This activity is significant because it is commonly used by malware such as RATs, bots, or Trojans to evade detection by allowing threats to pass through the Windows Defender antivirus engine. If confirmed malicious, this action could allow an attacker to execute malicious code without being detected by Windows Defender, leading to potential data exfiltration, further system compromise, or persistent access within the environment.

name: Powershell Defender Threat Actions Set to Allow
id: 7dd3ced1-dc48-4998-9bc2-57e6ae5efaa7
version: 1
creation_date: '2026-05-12'
modification_date: '2026-05-12'
author: Teoderick Contreras, Splunk
status: production
type: TTP
description: The following analytic detects the setting of the Windows Defender Threat Actions to allow. It leverages data from the Endpoint.Processes data model, specifically monitoring the execution of the `Set-MpPreference` cmdlet with the `-HighThreatDefaultAction`, `-ModerateThreatDefaultAction`, `-LowThreatDefaultAction`, and `-SevereThreatDefaultAction` parameters set to `6`. This activity is significant because it is commonly used by malware such as RATs, bots, or Trojans to evade detection by allowing threats to pass through the Windows Defender antivirus engine. If confirmed malicious, this action could allow an attacker to execute malicious code without being detected by Windows Defender, leading to potential data exfiltration, further system compromise, or persistent access within the environment.
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
    `process_powershell`
    Processes.process="*Set-MpPreference*"
    (
      Processes.process IN (
        "*-HighThreatDefaultAction*",
        "*-ModerateThreatDefaultAction*",
        "*-LowThreatDefaultAction*",
        "*-SevereThreatDefaultAction*"
      )
      Processes.process IN (
        "* 6*"
      )
    )
    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)`
    | `powershell_defender_threat_actions_set_to_allow_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: Limited false positives. However, tune based on scripts that may perform this action.
references:
    - https://www.broadcom.com/support/security-center/protection-bulletin/uac-0252-activity-delivering-shadowsniff-and-salatstealer-malware
    - https://bazaar.abuse.ch/browse/tag/SalatStealer/
drilldown_searches:
    - name: View the detection results for - "$dest$"
      search: '%original_detection_search% | search  dest = "$dest$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$dest$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") | 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"
finding:
    title: Process Commandline [$process$] that Set to Allow Windows Defender Threat Actions on [$dest$].
    entity:
        field: dest
        type: system
        score: 50
analytic_story:
    - Salat Stealer
asset_type: Endpoint
mitre_attack_id:
    - T1059.001
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/T1059.001/threat_allow_switch/threat_allow_salat.log
          source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
          sourcetype: XmlWinEventLog
      test_type: unit

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