Windows Powershell Import Applocker Policy

Description

The following analytic detects the import of Windows PowerShell Applocker cmdlets, specifically identifying the use of "Import-Module Applocker" and "Set-AppLockerPolicy" with an XML policy. It leverages PowerShell Script Block Logging (EventCode 4104) to capture and analyze script block text. This activity is significant as it may indicate an attempt to enforce restrictive Applocker policies, potentially used by malware like Azorult to disable antivirus products. If confirmed malicious, this could allow an attacker to bypass security controls, leading to further system compromise and persistence.

Query · spl

`powershell`
EventCode=4104
ScriptBlockText="*Import-Module Applocker*"
ScriptBlockText="*Set-AppLockerPolicy*"
ScriptBlockText="* -XMLPolicy *"
| fillnull
| stats count min(_time) as firstTime
              max(_time) as lastTime
  by dest signature signature_id
     user_id vendor_product EventID
     Guid Opcode Name
     Path ProcessID ScriptBlockId
     ScriptBlockText
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_powershell_import_applocker_policy_filter`

Implementation guide

To successfully implement this analytic, you will need to enable PowerShell Script Block Logging on some or all endpoints. Additional setup here https://help.splunk.com/en/security-offerings/splunk-user-behavior-analytics/get-data-in/5.4.1/add-other-data-to-splunk-uba/configure-powershell-logging-to-see-powershell-anomalies-in-splunk-uba.

Known false positives

  • administrators may execute this command that may cause some false positive.

Analyst notes

Known false positives: administrators may execute this command that may cause some false positive.

Raw source Windows Powershell Import Applocker Policy · SPL
Esc
Published by splunk/security_content ↗, licensed under Apache 2.0 ↗. Reproduced here unmodified. 
name: Windows Powershell Import Applocker Policy
id: 102af98d-0ca3-4aa4-98d6-7ab2b98b955a
version: 14
creation_date: '2022-06-30'
modification_date: '2026-06-29'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: |-
    The following analytic detects the import of Windows PowerShell Applocker cmdlets, specifically identifying the use of "Import-Module Applocker" and "Set-AppLockerPolicy" with an XML policy.
    It leverages PowerShell Script Block Logging (EventCode 4104) to capture and analyze script block text.
    This activity is significant as it may indicate an attempt to enforce restrictive Applocker policies, potentially used by malware like Azorult to disable antivirus products.
    If confirmed malicious, this could allow an attacker to bypass security controls, leading to further system compromise and persistence.
data_source:
    - Powershell Script Block Logging 4104
search: |-
    `powershell`
    EventCode=4104
    ScriptBlockText="*Import-Module Applocker*"
    ScriptBlockText="*Set-AppLockerPolicy*"
    ScriptBlockText="* -XMLPolicy *"
    | fillnull
    | stats count min(_time) as firstTime
                  max(_time) as lastTime
      by dest signature signature_id
         user_id vendor_product EventID
         Guid Opcode Name
         Path ProcessID ScriptBlockId
         ScriptBlockText
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `windows_powershell_import_applocker_policy_filter`
how_to_implement: To successfully implement this analytic, you will need to enable PowerShell Script Block Logging on some or all endpoints. Additional setup here https://help.splunk.com/en/security-offerings/splunk-user-behavior-analytics/get-data-in/5.4.1/add-other-data-to-splunk-uba/configure-powershell-logging-to-see-powershell-anomalies-in-splunk-uba.
known_false_positives: administrators may execute this command that may cause some false positive.
references:
    - https://app.any.run/tasks/a6f2ffe2-e6e2-4396-ae2e-04ea0143f2d8/
drilldown_searches:
    - name: View the detection results for - "$dest$" and "$user_id$"
      search: '%original_detection_search% | search  dest = "$dest$" user_id = "$user_id$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$dest$" and "$user_id$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$", "$user_id$") | 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: A suspicious powershell script with the ScriptBlockId [$ScriptBlockId$] containing Import-Module Applocker and Set-AppLockerPolicy commands to import Applocker policy was executed on host $dest$
        - field: user_id
          type: user
          score: 20
          message: A suspicious powershell script with the ScriptBlockId [$ScriptBlockId$] containing Import-Module Applocker and Set-AppLockerPolicy commands to import Applocker policy was executed on host $dest$ by user $user_id$
analytic_story:
    - Azorult
asset_type: Endpoint
mitre_attack_id:
    - T1059.001
    - T1685
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/import_applocker_policy/windows-powershell-xml2.log
          source: XmlWinEventLog:Microsoft-Windows-PowerShell/Operational
          sourcetype: XmlWinEventLog
      test_type: unit

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