O365 Compliance Content Search Started

SPLUNK detection rule by Mauricio Velazco, Splunk · Apache-2.0

The following analytic detects when a content search is initiated within the Office 365 Security and Compliance Center. It leverages the SearchCreated operation from the o365_management_activity logs under the SecurityComplianceCenter workload. This activity is significant as it may indicate an attempt to access sensitive organizational data, including emails and documents. If confirmed malicious, this could lead to unauthorized data access, potential data exfiltration, and compliance violations. Monitoring this behavior helps ensure the integrity and security of organizational data.

name: O365 Compliance Content Search Started
id: f4cabbc7-c19a-4e41-8be5-98daeaccbb50
version: 12
creation_date: '2024-04-17'
modification_date: '2026-05-13'
author: Mauricio Velazco, Splunk
status: production
type: TTP
description: The following analytic detects when a content search is initiated within the Office 365 Security and Compliance Center. It leverages the SearchCreated operation from the o365_management_activity logs under the SecurityComplianceCenter workload. This activity is significant as it may indicate an attempt to access sensitive organizational data, including emails and documents. If confirmed malicious, this could lead to unauthorized data access, potential data exfiltration, and compliance violations. Monitoring this behavior helps ensure the integrity and security of organizational data.
data_source: []
search: |-
    `o365_management_activity` Workload=SecurityComplianceCenter Operation=SearchCreated
      | rename user_id as user
      | fillnull
      | stats count min(_time) as firstTime max(_time) as lastTime
        BY signature dest user
           src vendor_account vendor_product
           ExchangeLocations Query
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `o365_compliance_content_search_started_filter`
how_to_implement: You must install the Splunk Microsoft Office 365 Add-on and ingest Office 365 management activity events.
known_false_positives: Compliance content searches may be executed for legitimate purposes, filter as needed.
references:
    - https://attack.mitre.org/techniques/T1114/002/
    - 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
drilldown_searches:
    - name: View the detection results for - "$user$"
      search: '%original_detection_search% | search  user = "$user$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$user$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$") | 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: 7d
      latest_offset: "0"
finding:
    title: A new compliance content search was started by $user$
    entity:
        field: user
        type: user
        score: 50
analytic_story:
    - Office 365 Collection Techniques
asset_type: O365 Tenant
mitre_attack_id:
    - T1114.002
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: cloud
security_domain: audit
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1114.002/o365_compliance_content_search_started/o365_compliance_content_search_started.log
          sourcetype: o365:management:activity
          source: o365
      test_type: unit

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

41459118-265d-4e44-a9f0-63eb90b1dad6

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