First-Contact External Email Senders

This query lists external email senders seen for the first time in the period (most recent first), surfacing new first-contact relationships, using the EmailEvents table.

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: microsoftthreatprotection
Log source service: emailevents

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Detection rules

First-Contact External Email Senders

Detection logic

Detection requirements

MITRE ATT&CK mappings

From the source

Licence

Authorship

Detection rules