Detection rules › Splunk
Azure AD New Federated Domain Added
The following analytic detects the addition of a new federated domain within an Azure Active Directory tenant. It leverages Azure AD AuditLogs to identify successful "Set domain authentication" operations. This activity is significant as it may indicate the use of the Azure AD identity federation backdoor technique, allowing an adversary to establish persistence. If confirmed malicious, the attacker could impersonate any user, bypassing password and MFA requirements, potentially leading to unauthorized access and control over the Azure AD environment.
Known false positives
- In most organizations, domain federation settings will be updated infrequently. Filter as needed.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Privilege Escalation | |
| Defense Impairment |
Telemetry coverage
| Platform | Record / event type |
|---|---|
| Azure | Set domain authentication |
Rules detecting the same action
These rules filter on the same operation.
- [Entra ID] Domain Federation Trust Settings Modified (Kusto)
- Azure AD New Custom Domain Added (Splunk)
- Azure Domain Federation Settings Modified (Sigma)
- Entra ID Custom Domain Added or Verified (Elastic)
- Entra ID Domain Federation Configuration Change (Elastic)
- Modified domain federation trust settings (Kusto)
- New onmicrosoft domain added to tenant (Kusto)
- New Root Certificate Authority Added (Sigma)
Rule body
name: Azure AD New Federated Domain Added
id: a87cd633-076d-4ab2-9047-977751a3c1a0
version: 15
creation_date: '2022-09-02'
modification_date: '2026-05-13'
author: Mauricio Velazco, Gowthamaraj Rajendran, Splunk
status: production
type: TTP
description: The following analytic detects the addition of a new federated domain within an Azure Active Directory tenant. It leverages Azure AD AuditLogs to identify successful "Set domain authentication" operations. This activity is significant as it may indicate the use of the Azure AD identity federation backdoor technique, allowing an adversary to establish persistence. If confirmed malicious, the attacker could impersonate any user, bypassing password and MFA requirements, potentially leading to unauthorized access and control over the Azure AD environment.
data_source:
- Azure Active Directory Set domain authentication
search: |-
`azure_monitor_aad` operationName="Set domain authentication" "properties.result"=success
| rename properties.* as *
| rename targetResources{}.displayName as domain
| rename userAgent as user_agent
| fillnull
| stats count min(_time) as firstTime max(_time) as lastTime
BY dest user src
vendor_account vendor_product user_agent
domain signature
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `azure_ad_new_federated_domain_added_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. This analytic was written to be used with the azure:monitor:aad sourcetype leveraging the AuditLogs log category.
known_false_positives: In most organizations, domain federation settings will be updated infrequently. Filter as needed.
references:
- https://www.mandiant.com/resources/remediation-and-hardening-strategies-microsoft-365-defend-against-apt29-v13
- https://o365blog.com/post/federation-vulnerability/
- https://www.inversecos.com/2021/11/how-to-detect-azure-active-directory.html
- https://www.mandiant.com/resources/blog/detecting-microsoft-365-azure-active-directory-backdoors
- https://attack.mitre.org/techniques/T1484/002/
finding:
title: A new federated domain, $domain$ , was added by $user$
entity:
field: user
type: user
score: 50
analytic_story:
- Azure Active Directory Persistence
- Scattered Lapsus$ Hunters
- Hellcat Ransomware
- Storm-0501 Ransomware
asset_type: Azure Active Directory
mitre_attack_id:
- T1484.002
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
category: cloud
security_domain: threat
Stages and Predicates
Stage 1: search
`azure_monitor_aad` operationName="Set domain authentication" "properties.result"=success
Stage 2: rename
| rename properties.* as *
Stage 3: rename
| rename targetResources{}.displayName as domain
Stage 4: rename
| rename userAgent as user_agent
Stage 5: fillnull
| fillnull
Stage 6: stats
| stats count min(_time) as firstTime max(_time) as lastTime
BY dest user src
vendor_account vendor_product user_agent
domain signature
Stage 7: search
| `security_content_ctime(firstTime)`
Stage 8: search
| `security_content_ctime(lastTime)`
Stage 9: search
| `azure_ad_new_federated_domain_added_filter`
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
operationName | eq |
| field:"operationName" kind:eq |
properties.result | eq |
| field:"properties.result" kind:eq value:"success" |
sourcetype | eq |
| field:"sourcetype" kind:eq value:"azure:monitor:aad" |