ID | Technique | Tactic |
---|---|---|
T1114 | Email Collection | Collection |
T1114.002 | Remote Email Collection | Collection |
Detection: O365 Compliance Content Search Exported
Description
The following analytic identifies when the results of a content search within the Office 365 Security and Compliance Center are exported. It uses the SearchExported operation from the SecurityComplianceCenter workload in the o365_management_activity data source. This activity is significant because exporting search results can involve sensitive or critical organizational data, potentially leading to data exfiltration. If confirmed malicious, an attacker could gain access to and exfiltrate sensitive information, posing a severe risk to the organization's data security and compliance posture.
Search
1`o365_management_activity` Workload=SecurityComplianceCenter Operation="SearchExported"
2| rename user_id as user
3| stats count earliest(_time) as firstTime latest(_time) as lastTime by Operation, ObjectId, ExchangeLocations, user, Query
4|`security_content_ctime(firstTime)`
5|`security_content_ctime(lastTime)`
6| `o365_compliance_content_search_exported_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_compliance_content_search_exported_filter | search * |
o365_compliance_content_search_exported_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
Compliance content searche exports may be executed for legitimate purposes, filter as needed.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
A new compliance content search export was started by $user$ | 42 | 60 | 70 |
References
-
https://learn.microsoft.com/en-us/purview/ediscovery-content-search-overview
-
https://learn.microsoft.com/en-us/purview/ediscovery-keyword-queries-and-search-conditions
-
https://learn.microsoft.com/en-us/purview/ediscovery-search-for-activities-in-the-audit-log
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