Windows Firewall Rule Added via netsh.exe
Flags netsh.exe executions that add Windows firewall rules, indicating potential attacker-controlled network access changes.
- Product
- windows
- Category
- process_creation
- Author
- Markus Neis, Sander Wiebing (SigmaHQ), DRL 1.1
- Published
- 2019-01-29
- Updated
- 2026-07-30
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 identifies process executions of netsh.exe where the command line includes terms for adding a firewall rule. Attackers may use netsh to create inbound allow rules that facilitate persistence, remote access, or bypassing host-based network controls. The detection relies on Windows process creation telemetry, matching the netsh.exe executable and specific firewall add command-line content.
Reporting behind it
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: Windows Firewall Rule Added via netsh.exe
id: b196d28f-d9c8-4518-aaa1-aab00c063c33
status: test
description: This rule identifies process executions of netsh.exe where the command line includes terms for adding a firewall rule. Attackers may use netsh to create inbound allow rules that facilitate persistence, remote access, or bypassing host-based network controls. The detection relies on Windows process creation telemetry, matching the netsh.exe executable and specific firewall add command-line content.
references:
- https://web.archive.org/web/20190508165435/https://www.operationblockbuster.com/wp-content/uploads/2016/02/Operation-Blockbuster-RAT-and-Staging-Report.pdf
- https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_netsh_fw_add_rule.yml
author: Markus Neis, Sander Wiebing, Huntrule Team
date: 2019-01-29
modified: 2023-02-10
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:
- Legitimate administration activity
- Software installations
level: medium
license: DRL-1.1
related:
- id: cd5cfd80-aa5f-44c0-9c20-108c4ae12e3c
type: derived