Detection rules › Splunk
Windows Impair Defense Add Xml Applocker Rules
The following analytic detects the use of a PowerShell commandlet to import an AppLocker XML policy. This behavior is identified by monitoring processes that execute the "Import-Module Applocker" and "Set-AppLockerPolicy" commands with the "-XMLPolicy" parameter. This activity is significant because it can indicate an attempt to disable or bypass security controls, as seen in the Azorult malware. If confirmed malicious, this could allow an attacker to disable antivirus products, leading to further compromise and persistence within the environment.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Defense Impairment | T1685 Disable or Modify Tools |
Event coverage
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Security-Auditing | Event ID 4688 | A new process has been created. |
Rule body splunk
name: Windows Impair Defense Add Xml Applocker Rules
id: 467ed9d9-8035-470e-ad5e-ae5189283033
version: 10
creation_date: '2022-06-28'
modification_date: '2026-05-13'
author: Teoderick Contreras, Splunk
status: production
type: Hunting
description: The following analytic detects the use of a PowerShell commandlet to import an AppLocker XML policy. This behavior is identified by monitoring processes that execute the "Import-Module Applocker" and "Set-AppLockerPolicy" commands with the "-XMLPolicy" parameter. This activity is significant because it can indicate an attempt to disable or bypass security controls, as seen in the Azorult malware. If confirmed malicious, this could allow an attacker to disable antivirus products, leading to further compromise and persistence within the environment.
data_source:
- Sysmon EventID 1
- Windows Event Log Security 4688
- CrowdStrike ProcessRollup2
search: |-
| tstats `security_content_summariesonly` values(Processes.process) as process min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes
WHERE `process_powershell`
AND
Processes.process="*Import-Module Applocker*"
AND
Processes.process="*Set-AppLockerPolicy *"
AND
Processes.process="* -XMLPolicy *"
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_impair_defense_add_xml_applocker_rules_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: Administrators may execute this command that may cause some false positive.
references:
- https://app.any.run/tasks/a6f2ffe2-e6e2-4396-ae2e-04ea0143f2d8/
analytic_story:
- Azorult
asset_type: Endpoint
mitre_attack_id:
- 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/malware/azorult/sysmon.log
source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
sourcetype: XmlWinEventLog
test_type: unit
Stages and Predicates
Stage 1: tstats
| tstats `security_content_summariesonly` values(Processes.process) as process min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes
WHERE `process_powershell`
AND
Processes.process="*Import-Module Applocker*"
AND
Processes.process="*Set-AppLockerPolicy *"
AND
Processes.process="* -XMLPolicy *"
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_impair_defense_add_xml_applocker_rules_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.
| Field | Kind | Values |
|---|---|---|
Processes.original_file_name | eq |
|
Processes.process | eq |
|
Processes.process_name | eq |
|