Detectionhightest

Forfiles.EXE Child Process Masquerading

Detects the execution of "forfiles" from a non-default location, in order to potentially spawn a custom "cmd.exe" from the current working directory.

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Nasreddine Bencherchali (Nextron Systems), Anish BogatiCreated Fri Jan 05f53714ec-5077-420e-ad20-907ff9bb2958windows

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:
        # Notes:
        #   - The parent must not have CLI options
        #   - The Child Image must be named "cmd" as its hardcoded in the "forfiles" binary
        #   - The Child CLI will always contains "/c echo" as its hardcoded in the original "forfiles" binary
        ParentCommandLine|endswith:
            - '.exe'
            - '.exe"'
        Image|endswith: '\cmd.exe'
        CommandLine|startswith: '/c echo "'
    filter_main_parent_not_sys:
        ParentImage|contains:
            - ':\Windows\System32\'
            - ':\Windows\SysWOW64\'
        ParentImage|endswith: '\forfiles.exe'
        Image|contains:
            - ':\Windows\System32\'
            - ':\Windows\SysWOW64\'
        Image|endswith: '\cmd.exe'
    condition: selection and not 1 of filter_main_*