splunk_escuTTP

O365 ApplicationImpersonation Role Assigned

The following analytic detects the assignment of the ApplicationImpersonation role in Office 365 to a user or application. It uses the Office 365 Management Activity API to monitor Azure Active Directory audit logs for role assignment events. This activity is significant because the ApplicationImpersonation role allows impersonation of any user, enabling access to and modification of their mailbox. If confirmed malicious, an attacker could gain unauthorized access to sensitive information, manipulate mailbox data, and perform actions as a legitimate user, posing a severe security risk to the organization.

MITRE ATT&CK

T1098.002

Detection Query

`o365_management_activity` Workload=Exchange Operation="New-ManagementRoleAssignment" Role=ApplicationImpersonation
  | rename User as target_user
  | fillnull
  | stats count min(_time) as firstTime max(_time) as lastTime
    BY signature dest user
       src vendor_account vendor_product
       target_user
  | `security_content_ctime(lastTime)`
  | `o365_applicationimpersonation_role_assigned_filter`

Author

Mauricio Velazco, Splunk

Created

2026-03-10

Data Sources

O365

References

Tags

Office 365 Persistence MechanismsOffice 365 Collection TechniquesNOBELIUM Group

Raw Content

name: O365 ApplicationImpersonation Role Assigned
id: 49cdce75-f814-4d56-a7a4-c64ec3a481f2
version: 9
date: '2026-03-10'
author: Mauricio Velazco, Splunk
status: production
type: TTP
data_source:
    - O365
description: The following analytic detects the assignment of the ApplicationImpersonation role in Office 365 to a user or application. It uses the Office 365 Management Activity API to monitor Azure Active Directory audit logs for role assignment events. This activity is significant because the ApplicationImpersonation role allows impersonation of any user, enabling access to and modification of their mailbox. If confirmed malicious, an attacker could gain unauthorized access to sensitive information, manipulate mailbox data, and perform actions as a legitimate user, posing a severe security risk to the organization.
search: |-
    `o365_management_activity` Workload=Exchange Operation="New-ManagementRoleAssignment" Role=ApplicationImpersonation
      | rename User as target_user
      | fillnull
      | stats count min(_time) as firstTime max(_time) as lastTime
        BY signature dest user
           src vendor_account vendor_product
           target_user
      | `security_content_ctime(lastTime)`
      | `o365_applicationimpersonation_role_assigned_filter`
how_to_implement: You must install the Splunk Microsoft Office 365 Add-on and ingest Office 365 management activity events.
known_false_positives: While infrequent, the ApplicationImpersonation role may be granted for leigimate reasons, filter as needed.
references:
    - https://attack.mitre.org/techniques/T1098/002/
    - https://www.mandiant.com/resources/blog/remediation-and-hardening-strategies-for-microsoft-365-to-defend-against-unc2452
    - https://www.mandiant.com/media/17656
drilldown_searches:
    - name: View the detection results for - "$target_user$" and "$user$"
      search: '%original_detection_search% | search  target_user = "$target_user$" user = "$user$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$target_user$" and "$user$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$target_user$", "$user$") starthoursago=168  | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
rba:
    message: $user$ granted the ApplicationImpersonation role to $target_user$
    risk_objects:
        - field: target_user
          type: user
          score: 50
        - field: user
          type: user
          score: 50
    threat_objects: []
tags:
    analytic_story:
        - Office 365 Persistence Mechanisms
        - Office 365 Collection Techniques
        - NOBELIUM Group
    asset_type: O365 Tenant
    mitre_attack_id:
        - T1098.002
    product:
        - Splunk Enterprise
        - Splunk Enterprise Security
        - Splunk Cloud
    security_domain: threat
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1098.002/application_impersonation_role_assigned/application_impersonation_role_assigned.log
          source: O365
          sourcetype: o365:management:activity