Suspicious Port Forwarding Configuration via netsh portproxy (via process_creation)

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1090Proxy
Exfiltration
Impact

What it detects

This rule detects configuration of an IPv4 or IPv6 port forwarding rule using netsh portproxy. Fire Ant used netsh portproxy on servers and workstations to pivot and relay traffic deeper into segmented networks, sometimes abusing IPv6 to bypass IPv4 filtering. Network administrators may occasionally use portproxy for legitimate forwarding.

Reporting behind it

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Suspicious Port Forwarding Configuration via netsh portproxy (via process_creation)

Pivot detection · T1090 · 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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