Suspicious Firewall Port Opening via Netsh

ATT&CK techniques

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

What it detects

This rule detects netsh.exe being used to add a firewall port opening or allowed rule. In the WithSecure Catching Lazarus Part Two research the actor uses netsh firewall add portopening to permit inbound access for its tooling. Attackers weaken host firewall configuration to enable command and control or lateral movement.

Reporting behind it

Related detections9 linkedT1686 — drag to rearrange

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Suspicious Windows Firewall Rule Creation Masquerading as Network Discovery (via process_creation)

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Suspicious Firewall Rule Allowing SSH via New-NetFirewallRule During Ransomware

Suspicious iptables Port Redirect Rule via GRIMBOLT

Suspicious Firewall Allow Rule for TightVNC Server via netsh (via process_creation)

Suspicious Firewall Rule Added to Open RDP Port 3389 via netsh

Suspicious VMware PCI Device Disabled via Devcon

Possible Firewall Rule Manipulation via netsh advfirewall by FishMonger

Suspicious Firewall Port Opening via Netsh

Pivot detection · T1686 · 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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