SigmaHQ/rules/windows/process_creation/win_powershell_b64_shellcode.yml

title: PowerShell Base64 Encoded Shellcode
id: 2d117e49-e626-4c7c-bd1f-c3c0147774c8
description: Detects Base64 encoded Shellcode
status: experimental
references:
    - https://twitter.com/cyb3rops/status/1063072865992523776
author: Florian Roth
date: 2018/11/17
modified: 2020/09/01
tags:
    - attack.defense_evasion
    - attack.t1027
logsource:
    category: process_creation
    product: windows
detection:
    selection1:
        CommandLine|contains: 'AAAAYInlM'
    selection2:
        CommandLine|contains:
            - 'OiCAAAAYInlM'
            - 'OiJAAAAYInlM'
    condition: selection1 and selection2
falsepositives:
    - Unknown
level: critical
Converted Sysmon/1 and Security/4688 to generic process creation rules 2019-01-16 22:36:31 +00:00			`title: PowerShell Base64 Encoded Shellcode`
Added UUIDs to rules 2019-11-12 22:12:27 +00:00			`id: 2d117e49-e626-4c7c-bd1f-c3c0147774c8`
Converted Sysmon/1 and Security/4688 to generic process creation rules 2019-01-16 22:36:31 +00:00			`description: Detects Base64 encoded Shellcode`
			`status: experimental`
			`references:`
Increased indentation to 4 * Converted (to generic sigma) rules * Converter outputs by default with indentation 4 2019-03-01 23:14:20 +00:00			`- https://twitter.com/cyb3rops/status/1063072865992523776`
Converted Sysmon/1 and Security/4688 to generic process creation rules 2019-01-16 22:36:31 +00:00			`author: Florian Roth`
			`date: 2018/11/17`
review windows/process_creation part 4 2020-09-02 00:34:34 +00:00			`modified: 2020/09/01`
Converted Sysmon/1 and Security/4688 to generic process creation rules 2019-01-16 22:36:31 +00:00			`tags:`
Increased indentation to 4 * Converted (to generic sigma) rules * Converter outputs by default with indentation 4 2019-03-01 23:14:20 +00:00			`- attack.defense_evasion`
review windows/process_creation part 4 2020-09-02 00:34:34 +00:00			`- attack.t1027`
Converted Sysmon/1 and Security/4688 to generic process creation rules 2019-01-16 22:36:31 +00:00			`logsource:`
Increased indentation to 4 * Converted (to generic sigma) rules * Converter outputs by default with indentation 4 2019-03-01 23:14:20 +00:00			`category: process_creation`
			`product: windows`
Converted Sysmon/1 and Security/4688 to generic process creation rules 2019-01-16 22:36:31 +00:00			`detection:`
Increased indentation to 4 * Converted (to generic sigma) rules * Converter outputs by default with indentation 4 2019-03-01 23:14:20 +00:00			`selection1:`
Update win_powershell_b64_shellcode.yml 2020-10-15 21:20:29 +00:00			`CommandLine\|contains: 'AAAAYInlM'`
Increased indentation to 4 * Converted (to generic sigma) rules * Converter outputs by default with indentation 4 2019-03-01 23:14:20 +00:00			`selection2:`
Update win_powershell_b64_shellcode.yml 2020-10-15 21:20:29 +00:00			`CommandLine\|contains:`
			`- 'OiCAAAAYInlM'`
			`- 'OiJAAAAYInlM'`
Increased indentation to 4 * Converted (to generic sigma) rules * Converter outputs by default with indentation 4 2019-03-01 23:14:20 +00:00			`condition: selection1 and selection2`
Converted Sysmon/1 and Security/4688 to generic process creation rules 2019-01-16 22:36:31 +00:00			`falsepositives:`
Increased indentation to 4 * Converted (to generic sigma) rules * Converter outputs by default with indentation 4 2019-03-01 23:14:20 +00:00			`- Unknown`
Converted Sysmon/1 and Security/4688 to generic process creation rules 2019-01-16 22:36:31 +00:00			`level: critical`