Suspicious Network Connection from fsutil or Defender Client via network_connection

ATT&CK techniques

Priv Esc → C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1055.012Process Hollowing
Defense Evasion
- T1055.012Process Hollowing
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.001Web Protocols
Exfiltration
Impact

What it detects

This rule detects outbound network connections from fsutil.exe or the Defender client rmclient.exe, processes that do not normally initiate network traffic. The REMCOS watchdog component injects into these binaries to maintain a covert command-and-control channel. Such connections indicate likely process injection and should be investigated.

Reporting behind it

Related detections9 linkedT1071.001 — drag to rearrange

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Suspicious Network Connection from fsutil or Defender Client via network_connection

Pivot detection · T1071.001 · 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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