Detection rules › Splunk

Azure AD Multiple Service Principals Created by SP

Status
production
Severity
low
Group by
aws::recipientAccountId, signature, user, vendor_product
Author
Mauricio Velazco, Splunk
Source
github.com/splunk/security_content

The following analytic detects when a single service principal in Azure AD creates more than three unique OAuth applications within a 10-minute span. It leverages Azure AD audit logs, specifically monitoring the 'Add service principal' operation initiated by service principals. This behavior is significant as it may indicate an attacker using a compromised or malicious service principal to rapidly establish multiple service principals, potentially staging an attack. If confirmed malicious, this activity could facilitate network infiltration or expansion, allowing the attacker to gain unauthorized access and persist within the environment.

Known false positives

  • Certain users or applications may create multiple service principals in a short period of time for legitimate purposes. Filter as needed.

MITRE ATT&CK coverage

TacticTechniques
Persistence

Telemetry coverage

PlatformRecord / event type
AzureAdd service principal

Rules detecting the same action

These rules filter on the same operation.

Rule body

name: Azure AD Multiple Service Principals Created by SP
id: 66cb378f-234d-4fe1-bb4c-e7878ff6b017
version: 13
creation_date: '2024-02-14'
modification_date: '2026-05-13'
author: Mauricio Velazco, Splunk
status: production
type: Anomaly
description: The following analytic detects when a single service principal in Azure AD creates more than three unique OAuth applications within a 10-minute span. It leverages Azure AD audit logs, specifically monitoring the 'Add service principal' operation initiated by service principals. This behavior is significant as it may indicate an attacker using a compromised or malicious service principal to rapidly establish multiple service principals, potentially staging an attack. If confirmed malicious, this activity could facilitate network infiltration or expansion, allowing the attacker to gain unauthorized access and persist within the environment.
data_source:
    - Azure Active Directory Add service principal
search: |-
    `azure_monitor_aad` operationName="Add service principal" properties.initiatedBy.app.appId=*
      | rename properties.* as *
      | bucket span=10m _time
      | rename targetResources{}.displayName as displayName
      | rename targetResources{}.type as type
      | rename initiatedBy.app.displayName as src_user
      | rename userAgent as user_agent
      | fillnull
      | stats count min(_time) as firstTime max(_time) as lastTime dc(displayName) as unique_apps values(displayName) as displayName values(dest) as dest values(src) as src values(user) as user values(user_agent) as user_agent
        BY src_user vendor_account vendor_product
           signature
      | where unique_apps > 3
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `azure_ad_multiple_service_principals_created_by_sp_filter`
how_to_implement: You must install the latest version of Splunk Add-on for Microsoft Cloud Services from Splunkbase(https://splunkbase.splunk.com/app/3110/#/details). You must be ingesting Azure Active Directory events into your Splunk environment through an EventHub. This analytic was written to be used with the azure:monitor:aad sourcetype leveraging the AuditLogs log category.
known_false_positives: Certain users or applications may create multiple service principals in a short period of time for legitimate purposes. Filter as needed.
references:
    - https://attack.mitre.org/techniques/T1136/003/
    - https://www.microsoft.com/en-us/security/blog/2024/01/25/midnight-blizzard-guidance-for-responders-on-nation-state-attack/
intermediate_findings:
    entities:
        - field: src_user
          type: user
          score: 20
          message: Multiple OAuth applications were created by $src_user$ in a short period of time
analytic_story:
    - Azure Active Directory Persistence
    - NOBELIUM Group
asset_type: Azure Active Directory
mitre_attack_id:
    - T1136.003
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: cloud
security_domain: identity

Stages and Predicates

Stage 1: search

`azure_monitor_aad` operationName="Add service principal" properties.initiatedBy.app.appId=*

Stage 2: rename

| rename properties.* as *

Stage 3: bucket

| bucket span=10m _time

Stage 4: rename

| rename targetResources{}.displayName as displayName

Stage 5: rename

| rename targetResources{}.type as type

Stage 6: rename

| rename initiatedBy.app.displayName as src_user

Stage 7: rename

| rename userAgent as user_agent

Stage 8: fillnull

| fillnull

Stage 9: stats

| stats count min(_time) as firstTime max(_time) as lastTime dc(displayName) as unique_apps values(displayName) as displayName values(dest) as dest values(src) as src values(user) as user values(user_agent) as user_agent
    BY src_user vendor_account vendor_product
       signature

Stage 10: where

| where unique_apps > 3

Stage 11: search

| `security_content_ctime(firstTime)`

Stage 12: search

| `security_content_ctime(lastTime)`

Stage 13: search

| `azure_ad_multiple_service_principals_created_by_sp_filter`

Indicators

These rows show field, operator, and value matches.