Analysis

  • max time kernel
    172s
  • max time network
    301s
  • platform
    windows10_x64
  • resource
    win10-en-20210920
  • submitted
    29/09/2021, 00:24

General

  • Target
    invoice_2818144.vbs
  • Size 226B
  • Sample210929-ap75vsddan
  • SHA256 cb77b93150cb0f7fe65ce8a7e2a5781e727419451355a7736db84109fa215a89
  • MD5 SHA1 SHA512

Malware Config

Extracted

Family
  • remcos

Version
  • 3.2.1 Pro

Botnet
  • RemoteHost

C2
  • snackebay.ddns.net:7676

Attributes
  • audio_folder

    MicRecords

  • audio_path

    %AppData%

  • audio_record_time

    5

  • connect_delay

    0

  • connect_interval

    1

  • copy_file

    remcos.exe

  • copy_folder

    Remcos

  • delete_file

    false

  • hide_file

    false

  • hide_keylog_file

    false

  • install_flag

    false

  • install_path

    %AppData%

  • keylog_crypt

    false

  • keylog_file

    logs.dat

  • keylog_flag

    false

  • keylog_folder

    remcos

  • keylog_path

    %AppData%

  • mouse_option

    false

  • mutex

    Remasascos-LVXDHO

  • screenshot_crypt

    false

  • screenshot_flag

    false

  • screenshot_folder

    Screenshots

  • screenshot_path

    %AppData%

  • screenshot_time

    10

  • startup_value

    Remcos

  • take_screenshot_option

    false

  • take_screenshot_time

    5

  • take_screenshot_title

    notepad;solitaire;

Signatures

  • Registers COM server for autorun 1 TTPs
  • Remcos

    Remcos is a closed-source remote control and surveillance software.

  • Blocklisted process makes network request 3 IoCs
  • Drops startup file 2 IoCs
  • Loads dropped DLL 4 IoCs
  • Suspicious use of SetThreadContext 3 IoCs
  • Drops file in Windows directory 1 IoCs
  • Enumerates physical storage devices 1 TTPs

    Attempts to interact with connected storage/optical drive(s). Likely ransomware behaviour.

  • Modifies registry class 17 IoCs
  • Suspicious use of WriteProcessMemory 51 IoCs

Processes

  • C:\Windows\System32\WScript.exe
    "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Local\Temp\invoice_2818144.vbs"
    1⤵
    • Blocklisted process makes network request
    • Suspicious use of WriteProcessMemory
    PID:3624
    • C:\Windows\SYSWOW64\WSCRIPT.EXE
      "C:\Windows\SYSWOW64\WSCRIPT.EXE" //b //e:vbscript "C:\Users\Admin\AppData\Local\Temp\invoice_2818144.vbs"
      2⤵
      • Drops startup file
      • Loads dropped DLL
      • Suspicious use of SetThreadContext
      • Suspicious use of WriteProcessMemory
      PID:4296
      • C:\Windows\SysWOW64\regsvr32.exe
        "C:\Windows\System32\regsvr32.exe" /I /S "C:\Users\Admin\AppData\Local\Temp\dynwrapx.dll"
        3⤵
        • Loads dropped DLL
        • Modifies registry class
        PID:3996
      • C:\Windows\winhlp32.exe
        "C:\Windows\winhlp32.exe"
        3⤵
        • Drops file in Windows directory
        • Modifies registry class
        • Suspicious use of WriteProcessMemory
        PID:4052
        • C:\Windows\SysWOW64\WScript.exe
          "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Local\Temp\fknposccdrxufeqxvxheqn.vbs"
          4⤵
            PID:736
        • C:\Windows\SysWOW64\regsvr32.exe
          "C:\Windows\System32\regsvr32.exe" /I /S "C:\Users\Admin\AppData\Local\Temp\dynwrapx.dll"
          3⤵
          • Loads dropped DLL
          • Modifies registry class
          PID:3968
        • C:\Windows\winhlp32.exe
          "C:\Windows\winhlp32.exe"
          3⤵
            PID:4380
          • C:\Windows\SysWOW64\regsvr32.exe
            "C:\Windows\System32\regsvr32.exe" /I /S "C:\Users\Admin\AppData\Local\Temp\dynwrapx.dll"
            3⤵
            • Loads dropped DLL
            • Modifies registry class
            PID:4360
          • C:\Windows\winhlp32.exe
            "C:\Windows\winhlp32.exe"
            3⤵
              PID:4568

        Network

              MITRE ATT&CK Enterprise v6

              Replay Monitor

              Loading Replay Monitor...

              Downloads

              memory/4052-128-0x0000000000400000-0x0000000000479000-memory.dmp

              memory/4052-121-0x0000000000400000-0x0000000000479000-memory.dmp

              memory/4296-127-0x0000000004FB0000-0x0000000004FB1000-memory.dmp

              memory/4380-135-0x0000000000400000-0x0000000000479000-memory.dmp

              memory/4568-140-0x0000000000400000-0x0000000000479000-memory.dmp