title: Powershell Used To Disable Windows Defender AV Security Monitoring
author: ok @securonix invrep-de, oscd.community, frack113
date: 2020/10/12
description: Detects attackers attempting to disable Windows Defender using Powershell
detection:
    SELECTION_1:
        EventID: 1
    SELECTION_10:
        CommandLine: '*WinDefend*'
    SELECTION_11:
        CommandLine: '*start=disabled*'
    SELECTION_2:
        Image: '*\powershell.exe'
    SELECTION_3:
        CommandLine: '*-DisableBehaviorMonitoring $true*'
    SELECTION_4:
        CommandLine: '*-DisableRuntimeMonitoring $true*'
    SELECTION_5:
        CommandLine: '*sc*'
    SELECTION_6:
        CommandLine: '*stop*'
    SELECTION_7:
        CommandLine: '*WinDefend*'
    SELECTION_8:
        CommandLine: '*sc*'
    SELECTION_9:
        CommandLine: '*config*'
    condition: (SELECTION_1 and ((SELECTION_2 and (SELECTION_3 or SELECTION_4)) or
        (SELECTION_5 and SELECTION_6 and SELECTION_7) or (SELECTION_8 and SELECTION_9
        and SELECTION_10 and SELECTION_11)))
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.
id: a7ee1722-c3c5-aeff-3212-c777e4733217
level: high
logsource:
    category: process_creation
    product: windows
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
status: experimental
tags:
- attack.defense_evasion
- attack.t1089
- attack.t1562.001
yml_filename: win_powershell_disable_windef_av.yml
yml_path: /Users/user/Documents/YamatoSecurity/sigma/rules/windows/process_creation