User added to Teams and immediately uploads file

This hunting queries identifies users who are added to a Teams Channel or Teams chat and within 1 minute of being added upload a file via the chat. This might be an indicator of suspicious activity.

Detection logic

Detection requirements

Platform: Identity Provider Linux macOS Office Suite SaaS Windows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
Log source product: office365
Log source service: officeactivity_teams

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Detection rules

User added to Teams and immediately uploads file

Detection logic

Detection requirements

MITRE ATT&CK mappings

From the source

Licence

Authorship

Detection rules