Suspicious Startup Folder File Write (via file_event)

title: Suspicious Startup Folder File Write (via file_event)
id: 564f48e3-9814-5b05-aee4-aee0d65d7147
status: stable
description: This rule detects a General detection for files being created in the Windows startup directory. This could be an indicator of persistence.
references:
    - https://attack.mitre.org/techniques/T1547/001/
    - https://github.com/OTRF/detection-hackathon-apt29/issues/12
    - https://github.com/OTRF/ThreatHunter-Playbook/blob/2d4257f630f4c9770f78d0c1df059f891ffc3fec/docs/evals/apt29/detections/5.B.1_611FCA99-97D0-4873-9E51-1C1BA2DBB40D.md
author: Huntrule Team
date: 2026-02-07
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.t1547.001
logsource:
    product: windows
    category: file_event
detection:
    selection:
        TargetFilename|contains: '\Microsoft\Windows\Start Menu\Programs\StartUp'
    filter_main_update:
        - Image:
              - 'C:\Windows\System32\wuauclt.exe'
              - 'C:\Windows\uus\ARM64\wuaucltcore.exe'
        - TargetFilename|startswith:
              - 'C:\$WINDOWS.~BT\NewOS\'
              - 'C:\$WinREAgent\Scratch\Mount\'
    filter_optional_onenote:
        Image|endswith: '\ONENOTE.EXE'
        TargetFilename|endswith: '\Send to OneNote.lnk'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    - Unknown
level: medium