Name:O365 ApplicationImpersonation Role Assigned id:49cdce75-f814-4d56-a7a4-c64ec3a481f2 version:3 date:2024-09-30 author:Mauricio Velazco, Splunk status:production type:TTP 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. Data_source:
-O365
search:`o365_management_activity` Workload=Exchange Operation="New-ManagementRoleAssignment" Role=ApplicationImpersonation | rename User as target_user | stats max(_time) as lastTime by Operation, user, object, ObjectId, Role, 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:'$info_max_time$' tags: analytic_story: - 'Office 365 Persistence Mechanisms' - 'Office 365 Collection Techniques' - 'NOBELIUM Group' asset_type:O365 Tenant confidence:70 impact:80 message:$user$ granted the ApplicationImpersonation role to $target_user$ mitre_attack_id: - 'T1098' - 'T1098.002' observable: name:'target_user' type:'User' - role: - 'Victim' name:'user' type:'User' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' risk_score:56 required_fields: - '_time' - 'Workload' - 'Operation' - 'Role' - 'user' - 'User' - 'object' - 'ObjectId' security_domain:threat
