Detection rules › Sigma

Firewall configuration enumerated (PowerShell)

Status
experimental
Severity
medium
Log source
product windows, category ['ps_module', 'ps_classic_script', 'ps_script']
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker attempts to extract current Windows firewall configuration to prepare an attack.

MITRE ATT&CK coverage

Event coverage

Rule body yaml

title: Firewall configuration enumerated (PowerShell)
description: Detects scenarios where an attacker attempts to extract current Windows firewall configuration to prepare an attack.
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0007-Discovery/T1016-System%20Network%20Configuration%20Discovery
- https://docs.microsoft.com/en-us/powershell/module/netsecurity/get-netfirewallprofile?view=windowsserver2019-ps
tags:
- attack.discovery
- attack.t1016
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  category:
    - ps_module
    - ps_classic_script
    - ps_script
detection: # full command: Get-NetFirewallSetting
  selection_powershell_native:
    EventID: 800
    EventData|contains:
      - Get-NetFirewallProfile
      - Get-NetFirewallRule
      - Get-NetFirewallSetting

  selection_powershell_modern:
    EventID: 4103
    Payload|contains:
      - Get-NetFirewallProfile
      - Get-NetFirewallRule
      - Get-NetFirewallSetting

  selection_powershell_block:
    EventID: 4104
    ScriptBlockText|contains:
      - Get-NetFirewallProfile
      - Get-NetFirewallRule
      - Get-NetFirewallSetting

  condition: selection_powershell_native or selection_powershell_modern or selection_powershell_block
falsepositives:
- Administrator activity
level: medium

Stages and Predicates

Stage 0: condition

selection_powershell_native or selection_powershell_modern or selection_powershell_block

Stage 1: selection_powershell_native

selection_powershell_native:
  EventID: 800
  EventData|contains:
    - Get-NetFirewallProfile
    - Get-NetFirewallRule
    - Get-NetFirewallSetting

Stage 2: selection_powershell_modern

selection_powershell_modern:
  EventID: 4103
  Payload|contains:
    - Get-NetFirewallProfile
    - Get-NetFirewallRule
    - Get-NetFirewallSetting

Stage 3: selection_powershell_block

selection_powershell_block:
  EventID: 4104
  ScriptBlockText|contains:
    - Get-NetFirewallProfile
    - Get-NetFirewallRule
    - Get-NetFirewallSetting

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
EventDatamatch
  • Get-NetFirewallProfile
  • Get-NetFirewallRule
  • Get-NetFirewallSetting
Payloadmatch
  • Get-NetFirewallProfile
  • Get-NetFirewallRule corpus 2 (sigma 2)
  • Get-NetFirewallSetting
ScriptBlockTextmatch
  • Get-NetFirewallProfile
  • Get-NetFirewallRule
  • Get-NetFirewallSetting