Potentially Suspicious Windows App Behavior (via process_creation)

title: Potentially Suspicious Windows App Behavior (via process_creation)
id: 4c50e32b-d399-527f-b108-546ec773eeff
status: stable
description: This rule detects potentially anomalous child process of applications launched from inside the WindowsApps directory. This could be a sign of a rogue ".appx" package installation/execution
references:
    - https://news.sophos.com/en-us/2021/11/11/bazarloader-call-me-back-attack-abuses-windows-10-apps-mechanism/
    - https://www.sentinelone.com/labs/inside-malicious-windows-apps-for-malware-deployment/
author: Huntrule Team
date: 2026-02-13
tags:
    - attack.stealth
    - attack.execution
    - attack.t1204
logsource:
    product: windows
    category: process_creation
detection:
    selection_parent:
        ParentImage|contains: 'C:\Program Files\WindowsApps\'
    selection_susp_img:
        Image|endswith:
            - '\cmd.exe'
            - '\cscript.exe'
            - '\mshta.exe'
            - '\powershell.exe'
            - '\powershell_ise.exe'
            - '\pwsh.exe'
            - '\regsvr32.exe'
            - '\rundll32.exe'
            - '\wscript.exe'
    selection_susp_cli:
        CommandLine|contains:
            - 'cmd /c'
            - 'Invoke-'
            - 'Base64'
    filter_optional_terminal:
        ParentImage|contains: ':\Program Files\WindowsApps\Microsoft.WindowsTerminal'
        ParentImage|endswith: '\WindowsTerminal.exe'
        Image|endswith:
            - '\powershell.exe'
            - '\cmd.exe'
            - '\pwsh.exe'
    filter_optional_sysinternals:
        ParentImage|startswith: 'C:\Program Files\WindowsApps\Microsoft.SysinternalsSuite'
        Image|endswith: '\cmd.exe'
    condition: selection_parent and 1 of selection_susp_* and not 1 of filter_optional_*
falsepositives:
    - Unknown
level: medium