Network Connections from the Command Line with no Parameters

SIGMA detection rule by RedCanary, Sigma formatting by Micah Babinski · GPL-3.0

It is unusual for these processes to attempt network connections with an empty command line, which can indicate malicious command and control (C2) activity. Part of the RedCanary 2024 Threat Detection Report.

title: Network Connections from the Command Line with no Parameters
id: 1b49c5af-3774-4364-9c49-827fd59417cb
status: experimental
description: |
    It is unusual for these processes to attempt network connections with an empty command line, 
    which can indicate malicious command and control (C2) activity. Part of the RedCanary 2024 
    Threat Detection Report.
references:
    - https://redcanary.com/threat-detection-report/threats/raspberry-robin/
author: RedCanary, Sigma formatting by Micah Babinski
date: 2024/03/21
tags:
    - attack.command_and_control
logsource:
    category: network_connection
    product: windows
detection:
    selection:
        Image|endswith:
            - '\regsvr32.exe'
            - '\rundll32.exe'
            - '\dllhost.exe'
        CommandLine: null
    condition: selection
falsepositives:
    - Unknown
level: low

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Executable code, not a declarative rule

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Rejected pattern present

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