ID | Technique | Tactic |
---|---|---|
T1098 | Account Manipulation | Persistence |
T1098.003 | Additional Cloud Roles | Privilege Escalation |
Detection: Azure AD Privileged Role Assigned
Description
The following analytic detects the assignment of privileged Azure Active Directory roles to a user. It leverages Azure AD audit logs, specifically monitoring the "Add member to role" operation. This activity is significant as adversaries may assign privileged roles to compromised accounts to maintain persistence within the Azure AD environment. If confirmed malicious, this could allow attackers to escalate privileges, access sensitive information, and maintain long-term control over the Azure AD infrastructure.
Search
1`azure_monitor_aad` "operationName"="Add member to role"
2| rename properties.* as *
3| rename initiatedBy.user.userPrincipalName as initiatedBy
4| rename targetResources{}.modifiedProperties{}.newValue as roles
5| eval role=mvindex(roles,1)
6| stats count min(_time) as firstTime max(_time) as lastTime values(user) as user by initiatedBy, result, operationName, role
7| lookup privileged_azure_ad_roles azureadrole AS role OUTPUT isprvilegedadrole description
8| search isprvilegedadrole = True
9| `security_content_ctime(firstTime)`
10| `security_content_ctime(lastTime)`
11| `azure_ad_privileged_role_assigned_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
Azure Active Directory Add member to role | Azure | 'azure:monitor:aad' |
'Azure AD' |
N/A |
Macros Used
Name | Value |
---|---|
azure_monitor_aad | sourcetype=azure:monitor:aad |
azure_ad_privileged_role_assigned_filter | search * |
azure_ad_privileged_role_assigned_filter
is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Annotations
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 |
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. This analytic was written to be used with the azure:monitor:aad sourcetype leveraging the AuditLog log category.
Known False Positives
Administrators will legitimately assign the privileged roles users as part of administrative tasks. Filter as needed.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
A privileged Azure AD role was assigned for User $user$ initiated by $initiatedBy$ | 63 | 70 | 90 |
References
-
https://docs.microsoft.com/en-us/azure/active-directory/roles/concept-understand-roles
-
https://docs.microsoft.com/en-us/azure/active-directory/roles/permissions-reference
-
https://www.mandiant.com/resources/detecting-microsoft-365-azure-active-directory-backdoors
-
https://docs.microsoft.com/en-us/azure/active-directory/roles/security-planning
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: 4