sigmamediumHunting

Firewall Rule Update Via Netsh.EXE

Detects execution of netsh with the "advfirewall" and the "set" option in order to set new values for properties of a existing rule

Detection Query

selection_img:
  - Image|endswith: \netsh.exe
  - OriginalFileName: netsh.exe
selection_cli:
  CommandLine|contains|all:
    - " firewall "
    - " set "
condition: all of selection_*

Author

X__Junior (Nextron Systems)

Created

2023-07-18

Data Sources

windowsProcess Creation Events

Platforms

windows

References

https://ss64.com/nt/netsh.html

Tags

attack.defense-evasion

Raw Content

title: Firewall Rule Update Via Netsh.EXE
id: a70dcb37-3bee-453a-99df-d0c683151be6
status: test
description: Detects execution of netsh with the "advfirewall" and the "set" option in order to set new values for properties of a existing rule
references:
    - https://ss64.com/nt/netsh.html
author: X__Junior (Nextron Systems)
date: 2023-07-18
tags:
    - attack.defense-evasion
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\netsh.exe'
        - OriginalFileName: 'netsh.exe'
    selection_cli:
        CommandLine|contains|all:
            # Example 1: netsh advfirewall firewall set rule "group=\"Network Discovery\" " new enable=Yes"
            # Example 2: netsh advfirewall firewall set rule "group=\"File and Printer Sharing\" " new enable=Yes"
            - ' firewall '
            - ' set '
    condition: all of selection_*
falsepositives:
    - Legitimate administration activity
    - Software installations and removal
level: medium