ID | Technique | Tactic |
---|---|---|
T1003.002 | Security Account Manager | Credential Access |
Detection: Azure AD Privileged Graph API Permission Assigned
Description
The following analytic detects the assignment of high-risk Graph API permissions in Azure AD, specifically Application.ReadWrite.All, AppRoleAssignment.ReadWrite.All, and RoleManagement.ReadWrite.Directory. It uses azure_monitor_aad data to scan AuditLogs for 'Update application' operations, identifying when these permissions are assigned. This activity is significant as it grants broad control over Azure AD, including application and directory settings. If confirmed malicious, it could lead to unauthorized modifications and potential security breaches, compromising the integrity and security of the Azure AD environment. Immediate investigation is required.
Search
1`azure_monitor_aad` category=AuditLogs operationName="Update application"
2| eval newvalue = mvindex('properties.targetResources{}.modifiedProperties{}.newValue',0)
3| spath input=newvalue
4| search "{}.RequiredAppPermissions{}.EntitlementId"="1bfefb4e-e0b5-418b-a88f-73c46d2cc8e9" OR "{}.RequiredAppPermissions{}.EntitlementId"="06b708a9-e830-4db3-a914-8e69da51d44f" OR "{}.RequiredAppPermissions{}.EntitlementId"="9e3f62cf-ca93-4989-b6ce-bf83c28f9fe8"
5| eval Permissions = '{}.RequiredAppPermissions{}.EntitlementId'
6| stats count earliest(_time) as firstTime latest(_time) as lastTime values(Permissions) by user, object, user_agent, operationName
7| `security_content_ctime(firstTime)`
8| `security_content_ctime(lastTime)`
9| `azure_ad_privileged_graph_api_permission_assigned_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
Azure Active Directory Update application | Azure | 'azure:monitor:aad' |
'Azure AD' |
N/A |
Macros Used
Name | Value |
---|---|
azure_monitor_aad | sourcetype=azure:monitor:aad |
azure_ad_privileged_graph_api_permission_assigned_filter | search * |
azure_ad_privileged_graph_api_permission_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
Privileged Graph API permissions may be assigned for legitimate purposes. Filter as needed.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
User $user$ assigned privileged Graph API permissions to $object$ | 54 | 90 | 60 |
References
-
https://learn.microsoft.com/en-us/graph/permissions-reference
-
https://posts.specterops.io/azure-privilege-escalation-via-azure-api-permissions-abuse-74aee1006f48
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: 2