Detectionmediumtest

Suspicious WindowsTerminal Child Processes

Detects suspicious children spawned via the Windows Terminal application which could be a sign of persistence via WindowsTerminal (see references section)

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Nasreddine Bencherchali (Nextron Systems)Created Mon Jul 25Updated Tue Feb 148de89e52-f6e1-4b5b-afd1-41ecfa300d48windows

Log Source

WindowsProcess Creation

ProductWindows← raw: windows

CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic

detection:
    selection_parent:
        ParentImage|endswith:
            - '\WindowsTerminal.exe'
            - '\wt.exe'
    selection_susp:
        - Image|endswith:
              # Add more LOLBINS
              - '\rundll32.exe'
              - '\regsvr32.exe'
              - '\certutil.exe'
              - '\cscript.exe'
              - '\wscript.exe'
              - '\csc.exe'
        - Image|contains:
              # Add more suspicious paths
              - 'C:\Users\Public\'
              - '\Downloads\'
              - '\Desktop\'
              - '\AppData\Local\Temp\'
              - '\Windows\TEMP\'
        - CommandLine|contains:
              # Add more suspicious commandline
              - ' iex '
              - ' icm'
              - 'Invoke-'
              - 'Import-Module '
              - 'ipmo '
              - 'DownloadString('
              - ' /c '
              - ' /k '
              - ' /r '
    filter_builtin_visual_studio_shell:
        CommandLine|contains|all:
            - 'Import-Module'
            - 'Microsoft.VisualStudio.DevShell.dll'
            - 'Enter-VsDevShell'
    filter_open_settings:
        CommandLine|contains|all:
            - '\AppData\Local\Packages\Microsoft.WindowsTerminal_'
            - '\LocalState\settings.json'
    filter_vsdevcmd:
        CommandLine|contains|all:
            - 'C:\Program Files\Microsoft Visual Studio\'
            - '\Common7\Tools\VsDevCmd.bat'
    condition: all of selection_* and not 1 of filter_*