Potential Pikabot Infection - Suspicious Command Combinations Via Cmd.EXE

SIGMA detection rule by Alejandro Houspanossian ('@lekz86') · NOASSERTION

Detects the execution of concatenated commands via "cmd.exe". Pikabot often executes a combination of multiple commands via the command handler "cmd /c" in order to download and execute additional payloads. Commands such as "curl", "wget" in order to download extra payloads. "ping" and "timeout" are abused to introduce delays in the command execution and "Rundll32" is also used to execute malicious DLL files. In the observed Pikabot infections, a combination of the commands described above are used to orchestrate the download and execution of malicious DLL files.

title: Potential Pikabot Infection - Suspicious Command Combinations Via Cmd.EXE
id: e5144106-8198-4f6e-bfc2-0a551cc8dd94
status: test
description: |
    Detects the execution of concatenated commands via "cmd.exe". Pikabot often executes a combination of multiple commands via the command handler "cmd /c" in order to download and execute additional payloads.
    Commands such as "curl", "wget" in order to download extra payloads. "ping" and "timeout" are abused to introduce delays in the command execution and "Rundll32" is also used to execute malicious DLL files.
    In the observed Pikabot infections, a combination of the commands described above are used to orchestrate the download and execution of malicious DLL files.
references:
    - https://github.com/pr0xylife/Pikabot/blob/7f7723a74ca325ec54c6e61e076acce9a4b20538/Pikabot_30.10.2023.txt
    - https://github.com/pr0xylife/Pikabot/blob/7f7723a74ca325ec54c6e61e076acce9a4b20538/Pikabot_22.12.2023.txt
author: Alejandro Houspanossian ('@lekz86')
date: 2024-01-02
tags:
    - attack.command-and-control
    - attack.execution
    - attack.stealth
    - attack.t1059.003
    - attack.t1105
    - attack.t1218
    - detection.emerging-threats
logsource:
    product: windows
    category: process_creation
detection:
    selection_cmd:
        CommandLine|contains|all:
            - 'cmd'
            - '/c'
    selection_pipes:
        CommandLine|contains:
            - ' & '
            - ' || '
    selection_commands_1:
        CommandLine|contains:
            - ' curl'
            - ' wget'
            - ' timeout '
            - ' ping '
    selection_commands_2:
        CommandLine|contains:
            - ' rundll32'
            - ' mkdir '
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium

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