Detection: Windows Get Local Admin with FindLocalAdminAccess

Updated Date: 2024-09-30 ID: d2988160-3ce9-4310-b59d-905334920cdd Author: Gowthamaraj Rajendran, Mauricio Velazco, Splunk Type: TTP Product: Splunk Enterprise Security

Description

The following analytic detects the execution of the Find-LocalAdminAccess cmdlet using PowerShell Script Block Logging (EventCode=4104). This cmdlet is part of PowerView, a toolkit for Windows domain enumeration. Identifying the use of Find-LocalAdminAccess is crucial as adversaries may use it to find machines where the current user has local administrator access, facilitating lateral movement or privilege escalation. If confirmed malicious, this activity could allow attackers to target and compromise additional systems within the network, significantly increasing their control and access to sensitive information.

1`powershell` EventCode=4104 ScriptBlockText = "*Find-LocalAdminAccess*" 
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| `windows_get_local_admin_with_findlocaladminaccess_filter`

Data Source

Name Platform Sourcetype Source
Powershell Script Block Logging 4104 Windows icon Windows 'xmlwineventlog' 'XmlWinEventLog:Microsoft-Windows-PowerShell/Operational'

Macros Used

Name Value
powershell (source=WinEventLog:Microsoft-Windows-PowerShell/Operational OR source="XmlWinEventLog:Microsoft-Windows-PowerShell/Operational")
windows_get_local_admin_with_findlocaladminaccess_filter search *
windows_get_local_admin_with_findlocaladminaccess_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
T1087 Account Discovery Discovery
T1087.002 Domain Account Discovery
KillChainPhase.EXPLOITAITON
NistCategory.DE_CM
Cis18Value.CIS_10
Aquatic Panda
FIN13
APT41
BRONZE BUTLER
Chimera
Dragonfly
FIN13
FIN6
Fox Kitten
INC Ransom
Ke3chang
LAPSUS$
MuddyWater
OilRig
Poseidon Group
RedCurl
Sandworm Team
Scattered Spider
ToddyCat
Turla
Volt Typhoon
Wizard Spider
menuPass

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 Notable Yes
Rule Title %name%
Rule Description %description%
Notable Event Fields user, dest
Creates Risk Event True
This configuration file applies to all detections of type TTP. These detections will use Risk Based Alerting and generate Notable Events.

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 may leverage PowerSploit tools for legitimate reasons, filter as needed.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
Suspicious PowerShell Find-LocalAdminAccess was identified on endpoint $dest$ by user $user$. 25 50 50
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