Firewall Rule Deleted Via Netsh.EXE — Sigma Rule

Rule metadata and linked tags

Author: frack113. Source status: test; severity: medium. Source dates: 2022-08-14 / 2025-10-07.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 4c3f76247c1b0dd3216b9e55d22567d49fee3f261a5df1ec89b4810a4fea8ea3

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Firewall Rule Deleted Via Netsh.EXE
id: 1a5fefe6-734f-452e-a07d-fc1c35bce4b2
status: test
description: Detects the removal of a port or application rule in the Windows Firewall configuration using netsh
references:
    - https://app.any.run/tasks/8bbd5b4c-b82d-4e6d-a3ea-d454594a37cc/
author: frack113
date: 2022-08-14
modified: 2025-10-07
tags:
    - attack.defense-impairment
    - attack.t1686.003
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\netsh.exe'
        - OriginalFileName: 'netsh.exe'
    selection_cli:
        CommandLine|contains|all:
            - 'firewall'
            - 'delete '
    filter_optional_dropbox:
        ParentImage|endswith: '\Dropbox.exe'
        CommandLine|contains: 'name=Dropbox'
    filter_optional_avast:
        ParentImage|endswith: '\instup.exe'
        CommandLine|contains: 'advfirewall firewall delete rule name="Avast Antivirus Admin Client"'
    condition: all of selection_* and not 1 of filter_optional_*
falsepositives:
    - Legitimate administration activity
    - Software installations and removal
level: medium

Original YAML and metadata in JSON

False positives

• Legitimate administration activity
• Software installations and removal

Source references

• https://app.any.run/tasks/8bbd5b4c-b82d-4e6d-a3ea-d454594a37cc/