Suspicious Windows Defender Folder Exclusion Added Via Reg.EXE


Description

Detects the usage of "reg.exe" to add Defender folder exclusions. Qbot has been seen using this technique to add exclusions for folders within AppData and ProgramData.

Query · sigma

selection:
  Image|endswith: \reg.exe
  CommandLine|contains:
  - SOFTWARE\Microsoft\Windows Defender\Exclusions\Paths
  - SOFTWARE\Microsoft\Microsoft Antimalware\Exclusions\Paths
  CommandLine|contains|all:
  - 'ADD '
  - '/t '
  - 'REG_DWORD '
  - '/v '
  - '/d '
  - '0'
condition: selection

Known false positives

  • Legitimate use
Raw source Suspicious Windows Defender Folder Exclusion Added Via Reg.EXE · Sigma
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Published by SigmaHQ/sigma ↗, licensed under Detection Rule License 1.1 ↗. Reproduced here unmodified.
title: Suspicious Windows Defender Folder Exclusion Added Via Reg.EXE
id: 48917adc-a28e-4f5d-b729-11e75da8941f
status: test
description: Detects the usage of "reg.exe" to add Defender folder exclusions. Qbot has been seen using this technique to add exclusions for folders within AppData and ProgramData.
references:
    - https://thedfirreport.com/2022/02/07/qbot-likes-to-move-it-move-it/
    - https://redcanary.com/threat-detection-report/threats/qbot/
author: frack113
date: 2022-02-13
modified: 2023-02-04
tags:
    - attack.defense-impairment
    - attack.t1685
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith: '\reg.exe'
        CommandLine|contains:
            - 'SOFTWARE\Microsoft\Windows Defender\Exclusions\Paths'
            - 'SOFTWARE\Microsoft\Microsoft Antimalware\Exclusions\Paths'
        CommandLine|contains|all:
            - 'ADD '
            - '/t '
            - 'REG_DWORD '
            - '/v '
            - '/d '
            - '0'
    condition: selection
falsepositives:
    - Legitimate use
level: medium

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