SigmaHQ/rules/windows/process_creation/win_powershell_disable_windef_av.yml
2021-06-07 20:27:14 +02:00

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1.5 KiB
YAML

title: Powershell Used To Disable Windows Defender AV Security Monitoring
id: a7ee1722-c3c5-aeff-3212-c777e4733217
status: experimental
description: Detects attackers attempting to disable Windows Defender using Powershell
author: 'ok @securonix invrep-de, oscd.community, frack113'
date: 2020/10/12
modified: 2021/06/07
references:
- https://research.nccgroup.com/2020/06/23/wastedlocker-a-new-ransomware-variant-developed-by-the-evil-corp-group/
- https://rvsec0n.wordpress.com/2020/01/24/malwares-that-bypass-windows-defender/
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1562.001/T1562.001.md
tags:
- attack.defense_evasion
- attack.t1089 # legacy
- attack.t1562.001
logsource:
category: process_creation
product: windows
detection:
selection:
Image|endswith: '\powershell.exe'
CommandLine|contains:
- '-DisableBehaviorMonitoring $true'
- '-DisableRuntimeMonitoring $true'
tamper_cmd_stop:
CommandLine|contains|all:
- sc
- stop
- WinDefend
tamper_cmd_disabled:
CommandLine|contains|all:
- sc
- config
- WinDefend
- 'start=disabled'
condition: 1 of them
falsepositives:
- 'Minimal, for some older versions of dev tools, such as pycharm, developers were known to sometimes disable Windows Defender to improve performance, but this generally is not considered a good security practice.'
level: high