action: global
title: PowerShell Base64 Encoded Shellcode
description: Detects Base64 encoded Shellcode 
status: experimental
references:
    - https://twitter.com/cyb3rops/status/1063072865992523776
author: Florian Roth
date: 2018/11/17
tags:
    - attack.defense_evasion
    - attack.t1036
detection:
    condition: selection1 and selection2
falsepositives: 
    - Unknown
level: critical
---
# Windows Audit Log
logsource:
    product: windows
    service: security
    description: 'Requirements: Audit Policy : Detailed Tracking > Audit Process creation, Group Policy : Administrative Templates\System\Audit Process Creation'
detection:
    selection1:
        EventID: 4688
        ProcessCommandLine: '*AAAAYInlM*'
    selection2:
        ProcessCommandLine: 
            - '*OiCAAAAYInlM*'
            - '*OiJAAAAYInlM*'
---
# Sysmon
logsource:
    product: windows
    service: sysmon
detection:
    selection1:
        EventID: 1
        CommandLine: '*AAAAYInlM*'
    selection2:
        CommandLine: 
            - '*OiCAAAAYInlM*'
            - '*OiJAAAAYInlM*'