Suspicious Outbound Network Connection from msiexec.exe (via network_connection)

ATT&CK techniques

Priv Esc → Defense Evasion

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

What it detects

This rule detects the Windows installer msiexec.exe initiating outbound network traffic, a behavior seen when Zloader injects its Cobalt Strike stager into msiexec and beacons to command and control. Under normal conditions msiexec only reaches out to fetch packages from known distribution points. Unexpected connections from an injected msiexec process indicate hollowed execution and C2 activity.

Reporting behind it

Related detections9 linkedT1055.012 — drag to rearrange

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Suspicious Outbound Network Connection from msiexec.exe (via network_connection)

Pivot detection · T1055.012 · 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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