Detectionhightest

Rundll32 Execution Without CommandLine Parameters

Detects suspicious start of rundll32.exe without any parameters as found in CobaltStrike beacon activity

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Launch

Florian Roth (Nextron Systems)Created Thu May 27Updated Thu Aug 311775e15e-b61b-4d14-a1a3-80981298085awindows

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:
        CommandLine|endswith:
            - '\rundll32.exe'
            - '\rundll32.exe"'
            - '\rundll32'
    filter:
        ParentImage|contains:
            - '\AppData\Local\'
            - '\Microsoft\Edge\'
    condition: selection and not filter