title: Encoded IEX
author: Florian Roth
date: 2019/08/23
description: Detects a base64 encoded IEX command string in a process command line
detection:
    SELECTION_1:
        EventID: 1
    SELECTION_10:
        CommandLine: '*pZXggKE5ld*'
    SELECTION_11:
        CommandLine: '*SUVYIChOZX*'
    SELECTION_12:
        CommandLine: '*lFWCAoTmV3*'
    SELECTION_13:
        CommandLine: '*JRVggKE5ld*'
    SELECTION_2:
        CommandLine: '*SUVYIChb*'
    SELECTION_3:
        CommandLine: '*lFWCAoW*'
    SELECTION_4:
        CommandLine: '*JRVggKF*'
    SELECTION_5:
        CommandLine: '*aWV4IChb*'
    SELECTION_6:
        CommandLine: '*lleCAoW*'
    SELECTION_7:
        CommandLine: '*pZXggKF*'
    SELECTION_8:
        CommandLine: '*aWV4IChOZX*'
    SELECTION_9:
        CommandLine: '*lleCAoTmV3*'
    condition: (SELECTION_1 and (SELECTION_2 or SELECTION_3 or SELECTION_4 or SELECTION_5
        or SELECTION_6 or SELECTION_7 or SELECTION_8 or SELECTION_9 or SELECTION_10
        or SELECTION_11 or SELECTION_12 or SELECTION_13))
falsepositives:
- unknown
fields:
- CommandLine
- ParentCommandLine
id: 88f680b8-070e-402c-ae11-d2914f2257f1
level: critical
logsource:
    category: process_creation
    product: windows
modified: 2020/08/29
status: experimental
tags:
- attack.execution
- attack.t1059.001
- attack.t1086
yml_filename: win_encoded_iex.yml
yml_path: /Users/user/Documents/YamatoSecurity/sigma/rules/windows/process_creation