sigmamediumHunting

New Port Forwarding Rule Added Via Netsh.EXE

Detects the execution of netsh commands that configure a new port forwarding (PortProxy) rule

MITRE ATT&CK

lateral-movementdefense-evasioncommand-and-control

Detection Query

selection_img:
  - Image|endswith: \netsh.exe
  - OriginalFileName: netsh.exe
selection_cli_1:
  CommandLine|contains|all:
    - interface
    - portproxy
    - add
    - v4tov4
selection_cli_2:
  CommandLine|contains|all:
    - "i "
    - "p "
    - "a "
    - "v "
selection_cli_3:
  CommandLine|contains|all:
    - connectp
    - listena
    - c=
condition: selection_img and 1 of selection_cli_*

Author

Florian Roth (Nextron Systems), omkar72, oscd.community, Swachchhanda Shrawan Poudel

Created

2019-01-29

Data Sources

windowsProcess Creation Events

Platforms

windows

References

Tags

attack.lateral-movementattack.defense-evasionattack.command-and-controlattack.t1090

Raw Content

title: New Port Forwarding Rule Added Via Netsh.EXE
id: 322ed9ec-fcab-4f67-9a34-e7c6aef43614
status: test
description: Detects the execution of netsh commands that configure a new port forwarding (PortProxy) rule
references:
    - https://www.fireeye.com/blog/threat-research/2019/01/bypassing-network-restrictions-through-rdp-tunneling.html
    - https://adepts.of0x.cc/netsh-portproxy-code/
    - https://www.dfirnotes.net/portproxy_detection/
author: Florian Roth (Nextron Systems), omkar72, oscd.community, Swachchhanda Shrawan Poudel
date: 2019-01-29
modified: 2023-09-01
tags:
    - attack.lateral-movement
    - attack.defense-evasion
    - attack.command-and-control
    - attack.t1090
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\netsh.exe'
        - OriginalFileName: 'netsh.exe'
    selection_cli_1:
        CommandLine|contains|all:
            - 'interface'
            - 'portproxy'
            - 'add'
            - 'v4tov4'
    selection_cli_2:
        CommandLine|contains|all:
            # Example: netsh I p a v l=8001 listena=127.0.0.1 connectp=80 c=192.168.1.1
            - 'i ' # interface
            - 'p ' # portproxy
            - 'a ' # add
            - 'v ' # v4tov4
    selection_cli_3:
        CommandLine|contains|all:
            - 'connectp'
            - 'listena'
            - 'c='
    condition: selection_img and 1 of selection_cli_*
falsepositives:
    - Legitimate administration activity
    - WSL2 network bridge PowerShell script used for WSL/Kubernetes/Docker (e.g. https://github.com/microsoft/WSL/issues/4150#issuecomment-504209723)
level: medium