O365 SharePoint Malware Detection

Original Source: [splunk source]
Name:O365 SharePoint Malware Detection
id:583c5de3-7709-44cb-abfc-0e828d301b59
version:2
date:2024-09-30
author:Steven Dick
status:production
type:TTP
Description:The following analytic identifies when a malicious file is detected within the SharePoint Online ecosystem. Attackers may stage and execute malicious files from within the Microsoft Office 365 ecosystem. Any detections from built-in Office 365 capabilities should be monitored and responded to appropriately. Certain premium Office 365 capabilities further enhance these detection and response functions.
Data_source:
  • -O365 Universal Audit Log
search:`o365_management_activity` Operation=FileMalwareDetected
| stats values(Workload) as category, values(SourceFileName) as file_name values(ObjectId) as file_path, values(VirusInfo) as signature, count, min(_time) as firstTime, max(_time) as lastTime by Id, UserId
| rename Id as signature_id, UserId as user
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `o365_sharepoint_malware_detection_filter`


how_to_implement:You must install the Splunk Microsoft Office 365 Add-on and ingest Office 365 management activity events.
known_false_positives:unknown
References:
  -https://learn.microsoft.com/en-us/microsoft-365/security/office-365-security/anti-malware-protection-for-spo-odfb-teams-about?view=o365-worldwide
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 ("$user$") 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:
    - 'Azure Active Directory Persistence'
    - 'Office 365 Account Takeover'
    - 'Ransomware Cloud'
  asset_type:O365 Tenant
  confidence:100
  impact:75
  message:SharePoint detected a potentially malicious file $file_name$
  mitre_attack_id:
    - 'T1204.002'
    - 'T1204'
  observable:
    name:'user'
    type:'User'
    - role:
      - 'Victim'
    name:'file_name'
    type:'File Name'
    - role:
      - 'Victim'
    name:'signature'
    type:'Other'
    - role:
      - 'Attacker'
  product:
    - 'Splunk Enterprise'
    - 'Splunk Enterprise Security'
    - 'Splunk Cloud'
  required_fields:
    - '_time'
    - 'Operation'
    - 'Workload'
    - 'SourceFileName'
    - 'ObjectId'
    - 'VirusInfo'
    - 'Id'
    - 'UserId'
  risk_score:75
  security_domain:threat

tests:
name:'True Positive Test'
 attack_data:
  data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1566/o365_various_alerts/o365_various_alerts.log
  sourcetype: o365:management:activity
  source: o365
manual_test:None