ID | Technique | Tactic |
---|---|---|
T1098 | Account Manipulation | Persistence |
T1098.003 | Additional Cloud Roles | Privilege Escalation |
Detection: O365 Privileged Role Assigned
Description
The following analytic identifies the assignment of sensitive and privileged Azure Active Directory roles to an Azure AD user. Adversaries and red teams alike may assign these roles to a compromised account to establish Persistence in an Azure AD environment. This detection leverages the O365 Universal Audit Log data source.
Search
1`o365_management_activity` Workload=AzureActiveDirectory Operation IN ("Add member to role.","Add eligible member to role.")
2| eval user = ObjectId, src_user = case(match(mvindex('Actor{}.ID',-1),"User"),mvindex('Actor{}.ID',0),match(mvindex('Actor{}.ID',-1),"ServicePrincipal"),mvindex('Actor{}.ID',3),true(),mvindex('Actor{}.ID',0)), object_name = mvindex('ModifiedProperties{}.NewValue', mvfind('ModifiedProperties{}.Name',"Role\.DisplayName")), object_id = mvindex('ModifiedProperties{}.NewValue', mvfind('ModifiedProperties{}.Name',"Role\.TemplateId")), signature = Operation, result = ResultStatus, category = mvindex('Target{}.ID',2)
3| stats count, min(_time) as firstTime, max(_time) as lastTime by src_user, user, category, result, object_name, object_id, signature
4| lookup privileged_azure_ad_roles azuretemplateid as object_id OUTPUT isprvilegedadrole
5| search isprvilegedadrole="TRUE" category="User"
6| `security_content_ctime(firstTime)`
7| `security_content_ctime(lastTime)`
8| `o365_privileged_role_assigned_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
N/A | N/A | N/A | N/A | N/A |
Macros Used
Name | Value |
---|---|
o365_management_activity | sourcetype=o365:management:activity |
o365_privileged_role_assigned_filter | search * |
o365_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 Splunk Microsoft Office 365 Add-on and ingest Office 365 management activity events.
Known False Positives
Administrators will legitimately assign the privileged roles users as part of administrative tasks. Microsoft Privileged Identity Management (PIM) may cause false positives / less accurate alerting.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
A privileged Azure AD role [$object_name$] was assigned to user $user$ by $src_user$ | 75 | 75 | 100 |
References
Detection Testing
Test Type | Status | Dataset | Source | Sourcetype |
---|---|---|---|---|
Validation | ✅ Passing | N/A | N/A | N/A |
Unit | ✅ Passing | Dataset | o365 |
o365:management:activity |
Integration | ✅ Passing | Dataset | o365 |
o365:management:activity |
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