Detection: Get ADDefaultDomainPasswordPolicy with Powershell Script Block

Updated Date: 2024-05-27 ID: 1ff7ccc8-065a-11ec-91e4-acde48001122 Author: Teoderick Contreras, Mauricio Velazco, Splunk Type: Hunting Product: Splunk Enterprise Security

Description

The following analytic detects the execution of the Get-ADDefaultDomainPasswordPolicy PowerShell cmdlet, which is used to retrieve the password policy in a Windows domain. This detection leverages PowerShell Script Block Logging (EventCode=4104) to identify the specific command execution. Monitoring this activity is significant as it can indicate an attempt to gather domain policy information, which is often a precursor to further malicious actions. If confirmed malicious, this activity could allow an attacker to understand password policies, aiding in password attacks or further domain enumeration.

Search

1`powershell` EventCode=4104 ScriptBlockText ="*Get-ADDefaultDomainPasswordPolicy*" 
2| stats count min(_time) as firstTime max(_time) as lastTime by EventCode ScriptBlockText Computer UserID 
3| rename Computer as dest, UserID as user 
4|  `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `get_addefaultdomainpasswordpolicy_with_powershell_script_block_filter`

Data Source

Name	Platform	Sourcetype	Source	Supported App
Powershell Script Block Logging 4104	Windows	`'xmlwineventlog'`	`'XmlWinEventLog:Microsoft-Windows-PowerShell/Operational'`	N/A

Macros Used

Name	Value
powershell	`(source=WinEventLog:Microsoft-Windows-PowerShell/Operational OR source="XmlWinEventLog:Microsoft-Windows-PowerShell/Operational")`
get_addefaultdomainpasswordpolicy_with_powershell_script_block_filter	`search *`

get_addefaultdomainpasswordpolicy_with_powershell_script_block_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK

+ Kill Chain Phases

+ NIST

+ CIS

- Threat Actors

ID	Technique	Tactic
T1201	Password Policy Discovery	Discovery

KillChainPhase.EXPLOITAITON

NistCategory.DE_AE

Cis18Value.CIS_10

Chimera

OilRig

Turla

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting	Value
Disabled	true
Cron Schedule	`0 * * * *`
Earliest Time	`-70m@m`
Latest Time	`-10m@m`
Schedule Window	`auto`
Creates Risk Event	False

This configuration file applies to all detections of type hunting.

Implementation

The following Hunting analytic requires PowerShell operational logs to be imported. Modify the powershell macro as needed to match the sourcetype or add index. This analytic is specific to 4104, or PowerShell Script Block Logging.

Known False Positives

Administrators or power users may use this command for troubleshooting.

Associated Analytic Story

Active Directory Discovery

Risk Based Analytics (RBA)

Risk Message	Risk Score	Impact	Confidence
Powershell process having commandline "Get-ADDefaultDomainPasswordPolicy" to query domain password policy on $dest$	9	30	30

The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

References

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-PowerShell/Operational`	`xmlwineventlog`
Integration	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-PowerShell/Operational`	`xmlwineventlog`

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub | Version: 3