Microsoft 365 - Potential Ransomware Activity (via threat_management)

title: Microsoft 365 - Potential Ransomware Activity (via threat_management)
id: 4787a3b2-2bfa-5fb6-a4a9-9b232f8f1a7e
status: stable
description: This rule detects when a Microsoft Cloud App Security reported when a user uploads files to the cloud that might be infected with ransomware.
references:
    - https://attack.mitre.org/techniques/T1486/
    - https://learn.microsoft.com/en-us/defender-cloud-apps/anomaly-detection-policy
    - https://learn.microsoft.com/en-us/defender-cloud-apps/policy-template-reference
author: Huntrule Team
date: 2026-04-02
tags:
    - attack.impact
    - attack.t1486
logsource:
    service: threat_management
    product: m365
detection:
    selection:
        eventSource: SecurityComplianceCenter
        eventName: 'Potential ransomware activity'
        status: success
    condition: selection
falsepositives:
    - Unknown
level: medium