title: Suspicious XOR Encoded PowerShell Command Line
author: Sami Ruohonen, Harish Segar (improvement)
date: 2018/09/05
description: Detects suspicious powershell process which includes bxor command, alternative
    obfuscation method to b64 encoded commands.
detection:
    SELECTION_1:
        EventID: 1
    SELECTION_2:
        Description: Windows PowerShell
    SELECTION_3:
        Product: PowerShell Core 6
    SELECTION_4:
        CommandLine: '*bxor*'
    SELECTION_5:
        CommandLine: '*join*'
    SELECTION_6:
        CommandLine: '*char*'
    condition: (SELECTION_1 and (SELECTION_2 or SELECTION_3) and (SELECTION_4 or SELECTION_5
        or SELECTION_6))
falsepositives:
- unknown
id: bb780e0c-16cf-4383-8383-1e5471db6cf9
level: medium
logsource:
    category: process_creation
    product: windows
modified: 2020/09/06
status: experimental
tags:
- attack.defense_evasion
- attack.t1086
- attack.t1059.001
- attack.t1140
- attack.t1027
yml_filename: win_powershell_xor_commandline.yml
yml_path: /Users/user/Documents/YamatoSecurity/sigma/rules/windows/process_creation