title: Invoke-Obfuscation VAR+ Launcher
author: Jonathan Cheong, oscd.community
date: 2020/10/15
description: Detects Obfuscated use of Environment Variables to execute PowerShell
detection:
    SELECTION_1:
        ScriptBlockText|re: .*cmd.{0,5}(?:\/c|\/r)(?:\s|)\"set\s[a-zA-Z]{3,6}.*(?:\{\d\}){1,}\\\"\s+?\-f(?:.*\)){1,}.*\"
    condition: SELECTION_1
falsepositives:
- Unknown
id: 0adfbc14-0ed1-11eb-adc1-0242ac120002
level: high
logsource:
    category: ps_script
    definition: Script block logging must be enabled
    product: windows
modified: 2021/10/16
references:
- https://github.com/Neo23x0/sigma/issues/1009
status: experimental
tags:
- attack.defense_evasion
- attack.t1027
- attack.execution
- attack.t1059.001
yml_filename: powershell_invoke_obfuscation_var_in_scriptblocktext.yml
yml_path: /Users/user/Documents/YamatoSecurity/sigma/rules/windows/powershell/powershell_script