Suspicious Outlook Process Spawning Network Utilities for NotDoor C2 (via process_creation)

ATT&CK techniques

C2 → Exfiltration

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.004DNS
Exfiltration
- T1041Exfiltration Over C2 Channel
Impact

What it detects

This rule detects the Outlook process spawning nslookup or curl, behavior used by the NotDoor backdoor to exfiltrate the username through DNS lookups and HTTP requests to attacker infrastructure. Outlook does not normally launch these command line network utilities.

Reporting behind it

Related detections9 linkedT1041 — drag to rearrange

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Suspicious Outlook Process Spawning Network Utilities for NotDoor C2 (via process_creation)

Pivot detection · T1041 · 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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