Detection: Windows Entra User Management Via Azure CLI

Description

This analytic detects the usage of the Azure CLI to interact with user accounts such as creating or deleting a user. Adversaries create new users so that their malicious activity does not interrupt the normal functions of the compromised users and can remain undetected. While legitimate administrative use is expected, anomalous execution patterns, unexpected users, or unusual parent processes should be treated as potential indicators of compromise and investigated promptly.

 1
 2| tstats `security_content_summariesonly`
 3  count min(_time) as firstTime
 4        max(_time) as lastTime
 5
 6from datamodel=Endpoint.Processes where
 7
 8Processes.process IN (
 9    "*az.cmd*",
10    "*azure.cli*"
11)
12Processes.process="*ad *"
13Processes.process="* user*"
14
15by Processes.process Processes.vendor_product Processes.user_id
16   Processes.process_hash Processes.parent_process_name
17   Processes.parent_process_exec Processes.action Processes.dest
18   Processes.process_current_directory Processes.process_path
19   Processes.process_integrity_level Processes.original_file_name
20   Processes.parent_process Processes.parent_process_path
21   Processes.parent_process_guid Processes.parent_process_id
22   Processes.process_guid Processes.process_id
23   Processes.user Processes.process_name
24
25
26| `drop_dm_object_name(Processes)`
27
28| `security_content_ctime(firstTime)`
29
30| `security_content_ctime(lastTime)`
31
32| `windows_entra_user_management_via_azure_cli_filter`

Data Source

Name Platform Sourcetype Source
CrowdStrike ProcessRollup2 Other 'crowdstrike:events:sensor' 'crowdstrike'
Sysmon EventID 1 Windows icon Windows 'XmlWinEventLog' 'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'
Windows Event Log Security 4688 Windows icon Windows 'XmlWinEventLog' 'XmlWinEventLog:Security'

Macros Used

Name Value
security_content_ctime convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)
windows_entra_user_management_via_azure_cli_filter search *
windows_entra_user_management_via_azure_cli_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
T1136 Create Account Persistence
T1078.004 Cloud Accounts Initial Access
T1098 Account Manipulation Persistence
Delivery
Exploitation
Installation
DE.AE
CIS 10

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 True
This configuration file applies to all detections of type anomaly. These detections will use Risk Based Alerting.

Implementation

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

Legitimate IT administrators commonly use the Azure CLI for managing user accounts. Filter alerts to exclude approved administrative or automated user management activities.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message:

Azure user management activity observed on $dest$ executed by $parent_process_name$ via commandline $process$.

Risk Object Risk Object Type Risk Score Threat Objects
dest system 20 process, process_name, parent_process_name

References

Detection Testing

Test Type Status Dataset Source Sourcetype
Validation Passing N/A N/A N/A
Unit Passing Dataset XmlWinEventLog:Security XmlWinEventLog
Integration ✅ Passing Dataset XmlWinEventLog:Security 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: 1