Suspicious ApplicationImpersonation Role Assigned to Mailbox Principal (via m365)
- Product
- m365
- Service
- exchange
- Author
- HuntRule
- Published
- 2026-10-13
- Updated
- 2026-10-13
ATT&CK techniques
Persistence → Priv EscRecon
Resource Dev
Initial Access
Execution
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects assignment of the Exchange ApplicationImpersonation management role. Midnight Blizzard used impersonation rights combined with malicious OAuth applications to read targeted mailboxes via Exchange Web Services.
Reporting behind it
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
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Also included
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