Suspicious New Firewall Rule Added Through Netsh.EXE (via process_creation)

title: Suspicious New Firewall Rule Added Through Netsh.EXE (via process_creation)
id: f840897c-fe02-538b-a4d6-529ac7eb9fbf
status: stable
description: This rule detects the addition of a new rule to the Windows firewall via netsh
references:
    - https://attack.mitre.org/techniques/T1686/003/
    - https://web.archive.org/web/20190508165435/https://www.operationblockbuster.com/wp-content/uploads/2016/02/Operation-Blockbuster-RAT-and-Staging-Report.pdf
author: Huntrule Team
date: 2026-03-27
tags:
    - attack.defense-impairment
    - attack.t1686.003
    - attack.s0246
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\netsh.exe'
        - OriginalFileName: 'netsh.exe'
    selection_cli:
        CommandLine|contains|all:
            - ' firewall '
            - ' add '
    filter_optional_dropbox:
        CommandLine|contains:
            - 'advfirewall firewall add rule name=Dropbox dir=in action=allow "program=?:\Program Files (x86)\Dropbox\Client\Dropbox.exe" enable=yes profile=Any'
            - 'advfirewall firewall add rule name=Dropbox dir=in action=allow "program=?:\Program Files\Dropbox\Client\Dropbox.exe" enable=yes profile=Any'
    condition: all of selection_* and not 1 of filter_optional_*
falsepositives:
    - Unknown
level: medium