Suspicious Inbox Rule Moving Mail to Junk for Concealment (via m365)

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1564.008Email Hiding Rules
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects creation or modification of a mailbox inbox rule that moves incoming messages to the junk email folder. Threat actors created such rules to hide fraud notifications and security alerts from the victim while automating financially driven attacks.

Reporting behind it

Related detections9 linkedT1564.008 — drag to rearrange

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Suspicious Inbox Rule Moving Mail to Junk for Concealment (via m365)

Pivot detection · T1564.008 · 9 related

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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