Try in Splunk Security Cloud

Description

The following analytic identifies the configuration of Azure Active Directory Applications in a manner that allows authentication from external tenants or personal accounts. This configuration can lead to inappropriate or malicious access of any data or capabilities the application is allowed to access. This detection leverages the O365 Universal Audit Log data source.

  • Type: TTP

  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud

  • Last Updated: 2024-04-11
  • Author: Steven Dick
  • ID: 942548a3-0273-47a4-8dbd-e5202437395c

Annotations

ATT&CK

ATT&CK

ID Technique Tactic
T1098.003 Additional Cloud Roles Persistence, Privilege Escalation
T1098 Account Manipulation Persistence, Privilege Escalation
Kill Chain Phase
  • Installation
  • Exploitation
NIST
  • DE.CM
CIS20
  • CIS 10
CVE 


1
2
3
4
5
6
7
8



`o365_management_activity` Workload=AzureActiveDirectory Operation IN ("Add application.","Update application.") ModifiedProperties{}.Name=AvailableToOtherTenants 
| eval result = case(match(mvindex('ModifiedProperties{}.NewValue',mvfind('ModifiedProperties{}.Name',"AvailableToOtherTenants")),"false"),"removed",true(),"added"), object_name=mvindex('Target{}.ID', 3), signature=Operation, object_attrs = "AvailableToOtherTenants", 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)) 
| search result = "added" 
| stats values(ActorIpAddress) as src, count, min(_time) as firstTime, max(_time) as lastTime by signature, user, object, object_name, object_attrs, result 
| `security_content_ctime(firstTime)`  
| `security_content_ctime(lastTime)` 
| `o365_application_available_to_other_tenants_filter`

Macros

The SPL above uses the following Macros:

:information_source: o365_application_available_to_other_tenants_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Required fields

List of fields required to use this analytic.

  • _time
  • Operation
  • ModifiedProperties{}.NewValue
  • ModifiedProperties{}.Name
  • UserId
  • Workload
  • Target{}.ID

How To Implement

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

Known False Positives

Business approved changes by known administrators.

Associated Analytic Story

RBA

Risk Score Impact Confidence Message
50.0 50 100 An Azure Application [$object_name$] was configured by [$user$] as accessible to external tenants.

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

Reference

Test Dataset

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 | version: 1