title: Powershell AMSI Bypass via .NET Reflection
id: 30edb182-aa75-42c0-b0a9-e998bb29067c
status: test
description: Detects Request to amsiInitFailed that can be used to disable AMSI Scanning
author: Markus Neis
references:
  - https://twitter.com/mattifestation/status/735261176745988096
  - https://www.hybrid-analysis.com/sample/0ced17419e01663a0cd836c9c2eb925e3031ffb5b18ccf35f4dea5d586d0203e?environmentId=120
date: 2018/08/17
modified: 2021/11/27
logsource:
  category: process_creation
  product: windows
detection:
  selection1:
    CommandLine|contains: 'System.Management.Automation.AmsiUtils'
  selection2:
    CommandLine|contains: 'amsiInitFailed'
  condition: selection1 and selection2
falsepositives:
  - Potential Admin Activity
level: high
tags:
  - attack.defense_evasion
  - attack.t1562.001
