Analysis

  • max time kernel
    148s
  • max time network
    118s
  • platform
    windows10_x64
  • resource
    win10v20210410
  • submitted
    10/08/2021, 13:59

General

  • Target
    4bbf2d108f7e10872a657f7395a09eeb.exe
  • Size 1.1MB
  • Sample210810-e79tkl16kj
  • SHA256 e391c863171dbe0a79e9ee01b3f221603e1dddb3938c3215980cd5b991578f4e
  • MD5 SHA1 SHA512

Malware Config

Extracted

Family
  • remcos

Version
  • 3.2.0 Pro

Botnet
  • RemoteHost

C2
  • 45.137.22.101:5888

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

    Remcos-3RVIAE

  • 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

  • Remcos

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

  • Looks for VirtualBox Guest Additions in registry 2 TTPs
  • Looks for VMWare Tools registry key 2 TTPs
  • Checks BIOS information in registry 2 TTPs 2 IoCs

    BIOS information is often read in order to detect sandboxing environments.

  • Uses the VBS compiler for execution 1 TTPs
  • Maps connected drives based on registry 3 TTPs 2 IoCs

    Disk information is often read in order to detect sandboxing environments.

  • Suspicious use of SetThreadContext 1 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Creates scheduled task(s) 1 TTPs 1 IoCs

    Schtasks is often used by malware for persistence or to perform post-infection execution.

  • Suspicious behavior: EnumeratesProcesses 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 1 IoCs
  • Suspicious use of WriteProcessMemory 15 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\4bbf2d108f7e10872a657f7395a09eeb.exe
    "C:\Users\Admin\AppData\Local\Temp\4bbf2d108f7e10872a657f7395a09eeb.exe"
    1⤵
    • Checks BIOS information in registry
    • Maps connected drives based on registry
    • Suspicious use of SetThreadContext
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:1016
    • C:\Windows\SysWOW64\schtasks.exe
      "C:\Windows\System32\schtasks.exe" /Create /TN "Updates\kzqTuNuE" /XML "C:\Users\Admin\AppData\Local\Temp\tmpC5F5.tmp"
      2⤵
      • Creates scheduled task(s)
      PID:2152
    • C:\Windows\Microsoft.NET\Framework\v4.0.30319\vbc.exe
      "C:\Windows\Microsoft.NET\Framework\v4.0.30319\vbc.exe"
      2⤵
        PID:1408

    Network

          MITRE ATT&CK Enterprise v6

          Replay Monitor

          Loading Replay Monitor...

          Downloads

          memory/1016-119-0x0000000002790000-0x0000000002791000-memory.dmp

          memory/1016-123-0x0000000008510000-0x00000000085E0000-memory.dmp

          memory/1016-118-0x0000000004D50000-0x0000000004D51000-memory.dmp

          memory/1016-114-0x00000000002C0000-0x00000000002C1000-memory.dmp

          memory/1016-120-0x0000000004EB0000-0x0000000004EB1000-memory.dmp

          memory/1016-121-0x0000000004D50000-0x000000000524E000-memory.dmp

          memory/1016-117-0x0000000005250000-0x0000000005251000-memory.dmp

          memory/1016-116-0x0000000004C00000-0x0000000004C01000-memory.dmp

          memory/1016-122-0x0000000005230000-0x0000000005241000-memory.dmp

          memory/1016-125-0x000000000DD70000-0x000000000DD71000-memory.dmp

          memory/1016-124-0x000000000ACD0000-0x000000000AD45000-memory.dmp

          memory/1408-128-0x0000000000400000-0x0000000000479000-memory.dmp

          memory/1408-132-0x0000000000400000-0x0000000000479000-memory.dmp