Detection: O365 Tenant Wide Admin Consent Granted

Updated Date: 2024-09-30 ID: 50eaabf8-5180-4e86-bfb2-011472c359fc Author: Mauricio Velazco, Splunk Type: TTP Product: Splunk Enterprise Security

Description

The following analytic identifies instances where admin consent is granted to an application within an Azure AD and Office 365 tenant. It leverages O365 audit logs, specifically events related to the admin consent action within the AzureActiveDirectory workload. This activity is significant because admin consent allows applications to access data across the entire tenant, potentially exposing vast amounts of organizational data. If confirmed malicious, an attacker could gain extensive and persistent access to organizational data, leading to data exfiltration, espionage, further malicious activities, and potential compliance violations.

Search

1`o365_management_activity` Operation="Consent to application."  
2| eval new_field=mvindex('ModifiedProperties{}.NewValue', 4) 
3| rex field=new_field "ConsentType: (?<ConsentType>[^\,]+)" 
4| rex field=new_field "Scope: (?<Scope>[^\,]+)"  
5| search  ConsentType = "AllPrincipals"  
6| stats count min(_time) as firstTime max(_time) as lastTime by Operation, user, object, ObjectId, ConsentType, Scope 
7| `security_content_ctime(firstTime)`  
8| `security_content_ctime(lastTime)` 
9| `o365_tenant_wide_admin_consent_granted_filter`

Data Source

Name	Platform	Sourcetype	Source
O365 Consent to application.	N/A	`'o365:management:activity'`	`'o365'`

Macros Used

Name	Value
o365_management_activity	`sourcetype=o365:management:activity`
o365_tenant_wide_admin_consent_granted_filter	`search *`

o365_tenant_wide_admin_consent_granted_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
T1098	Account Manipulation	Persistence
T1098.003	Additional Cloud Roles	Privilege Escalation

KillChainPhase.EXPLOITAITON

KillChainPhase.INSTALLATION

NistCategory.DE_CM

Cis18Value.CIS_10

HAFNIUM

Lazarus Group

LAPSUS$

Scattered Spider

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

This configuration file applies to all detections of type TTP. These detections will use Risk Based Alerting and generate Notable Events.

Implementation

You must install the Splunk Microsoft Office 365 Add-on and ingest Office 365 management activity events.

Known False Positives

Legitimate applications may be granted tenant wide consent, filter as needed.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message	Risk Score	Impact	Confidence
The $object$ application registration was granted tenant wide admin consent.	45	90	50

The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

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: 3