Detection: Azure AD New MFA Method Registered For User

Updated Date: 2026-05-13 ID: 2628b087-4189-403f-9044-87403f777a1b Author: Mauricio Velazco, Splunk Type: TTP Product: Splunk Enterprise Security

Description

The following analytic detects the registration of a new Multi-Factor Authentication (MFA) method for an Azure AD account. It leverages Azure AD AuditLogs to identify when a user registers new security information. This activity is significant because adversaries who gain unauthorized access to an account may add their own MFA method to maintain persistence. If confirmed malicious, this could allow attackers to bypass existing security controls, maintain long-term access, and potentially escalate their privileges within the environment.

Search

 1`azure_monitor_aad` category=AuditLogs operationName="User registered security info" properties.operationType=Add
 2  
 3| rename properties.* as *
 4  
 5| rename targetResources{}.* as *
 6  
 7| rename userAgent as user_agent
 8  
 9| fillnull
10  
11| stats count min(_time) as firstTime max(_time) as lastTime
12    BY action dest user
13       src vendor_account vendor_product
14       user_agent result resultDescription
15       signature
16  
17| `security_content_ctime(firstTime)`
18  
19| `security_content_ctime(lastTime)`
20  
21| `azure_ad_new_mfa_method_registered_for_user_filter`

Data Source

Name	Platform	Sourcetype	Source
Azure Active Directory User registered security info	Azure	`'azure:monitor:aad'`	`'Azure AD'`

Macros Used

Name	Value
security_content_ctime	`convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)`
azure_ad_new_mfa_method_registered_for_user_filter	`search *`

azure_ad_new_mfa_method_registered_for_user_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
T1556.006	Multi-Factor Authentication	Credential Access

Exploitation

Installation

DE.CM

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 Finding (Notable)	Yes
Rule Title	`%name%`
Rule Description	`%description%`
Notable Event Fields	user, dest
Creates Intermediate Finding (Risk Event)	No

TTP detections generate a Finding (Notable) and may generate Intermediate Findings (Risk Events) for associated entities.

Implementation

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

Newly onboarded users who are registering an MFA method for the first time will also trigger this detection.

Associated Analytic Story

Finding

Title	Entity Field	Entity Type	Risk Score
A new MFA method was registered for user $user$	user	user	50

Threat Objects

Field	Type
src	ip_address

References

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`Azure AD`	`azure:monitor:aad`
Integration	✅ Passing	Dataset	`Azure AD`	`azure:monitor:aad`

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: 14