Analysis

  • max time kernel
    148s
  • max time network
    152s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20240802-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20240802-enlocale:en-usos:windows10-2004-x64system
  • submitted
    04/09/2024, 10:51

General

  • Target
    b84685b177c7bbd6e54c0cd81f5ac41c02e2c77a400b71a830636f93a686eaaf.exe
  • Size 11.6MB
  • Sample240904-mxw4saybpp
  • SHA256 b84685b177c7bbd6e54c0cd81f5ac41c02e2c77a400b71a830636f93a686eaaf
  • MD5 SHA1 SHA512 SSDEEP

Malware Config

Extracted

Family
  • tofsee

C2
  • vanaheim.cn

  • jotunheim.name

Signatures

  • Tofsee

    Backdoor/botnet which carries out malicious activities based on commands from a C2 server.

  • Creates new service(s) 2 TTPs
  • Modifies Windows Firewall 2 TTPs 1 IoCs
  • Sets service image path in registry 2 TTPs 1 IoCs
  • Checks computer location settings 2 TTPs 1 IoCs

    Looks up country code configured in the registry, likely geofence.

  • Deletes itself 1 IoCs
  • Executes dropped EXE 1 IoCs
  • Drops file in System32 directory 2 IoCs
  • Suspicious use of SetThreadContext 1 IoCs
  • Launches sc.exe 3 IoCs

    Sc.exe is a Windows utlilty to control services on the system.

  • Enumerates physical storage devices 1 TTPs

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

  • Event Triggered Execution: Netsh Helper DLL 1 TTPs 3 IoCs

    Netsh.exe (also referred to as Netshell) is a command-line scripting utility used to interact with the network configuration of a system.

  • System Location Discovery: System Language Discovery 1 TTPs 9 IoCs

    Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

  • Modifies data under HKEY_USERS 6 IoCs
  • Suspicious use of WriteProcessMemory 23 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\b84685b177c7bbd6e54c0cd81f5ac41c02e2c77a400b71a830636f93a686eaaf.exe
    "C:\Users\Admin\AppData\Local\Temp\b84685b177c7bbd6e54c0cd81f5ac41c02e2c77a400b71a830636f93a686eaaf.exe"
    1⤵
    • Checks computer location settings
    • System Location Discovery: System Language Discovery
    • Suspicious use of WriteProcessMemory
    PID:2056
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\iawkjdec\
      2⤵
      • System Location Discovery: System Language Discovery
      PID:4420
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\ixpwbzew.exe" C:\Windows\SysWOW64\iawkjdec\
      2⤵
      • System Location Discovery: System Language Discovery
      PID:4464
    • C:\Windows\SysWOW64\sc.exe
      "C:\Windows\System32\sc.exe" create iawkjdec binPath= "C:\Windows\SysWOW64\iawkjdec\ixpwbzew.exe /d\"C:\Users\Admin\AppData\Local\Temp\b84685b177c7bbd6e54c0cd81f5ac41c02e2c77a400b71a830636f93a686eaaf.exe\"" type= own start= auto DisplayName= "wifi support"
      2⤵
      • Launches sc.exe
      • System Location Discovery: System Language Discovery
      PID:4560
    • C:\Windows\SysWOW64\sc.exe
      "C:\Windows\System32\sc.exe" description iawkjdec "wifi internet conection"
      2⤵
      • Launches sc.exe
      • System Location Discovery: System Language Discovery
      PID:2040
    • C:\Windows\SysWOW64\sc.exe
      "C:\Windows\System32\sc.exe" start iawkjdec
      2⤵
      • Launches sc.exe
      • System Location Discovery: System Language Discovery
      PID:2912
    • C:\Windows\SysWOW64\netsh.exe
      "C:\Windows\System32\netsh.exe" advfirewall firewall add rule name="Host-process for services of Windows" dir=in action=allow program="C:\Windows\SysWOW64\svchost.exe" enable=yes>nul
      2⤵
      • Modifies Windows Firewall
      • Event Triggered Execution: Netsh Helper DLL
      • System Location Discovery: System Language Discovery
      PID:4984
  • C:\Windows\SysWOW64\iawkjdec\ixpwbzew.exe
    C:\Windows\SysWOW64\iawkjdec\ixpwbzew.exe /d"C:\Users\Admin\AppData\Local\Temp\b84685b177c7bbd6e54c0cd81f5ac41c02e2c77a400b71a830636f93a686eaaf.exe"
    1⤵
    • Executes dropped EXE
    • Suspicious use of SetThreadContext
    • System Location Discovery: System Language Discovery
    • Suspicious use of WriteProcessMemory
    PID:220
    • C:\Windows\SysWOW64\svchost.exe
      svchost.exe
      2⤵
      • Sets service image path in registry
      • Deletes itself
      • Drops file in System32 directory
      • System Location Discovery: System Language Discovery
      • Modifies data under HKEY_USERS
      PID:1560

Network

        MITRE ATT&CK Enterprise v15

        Replay Monitor

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        Downloads

        ixpwbzew.exe

        • Path C:\Users\Admin\AppData\Local\Temp\ixpwbzew.exe
        • Size 10.5MB
        • SHA256 21a5e8cf356706a639eee50ea97cecef91685eb906921245c314ac50950b9825
        • MD5 SHA1 SHA512 SSDEEP

        memory/220-11-0x0000000000400000-0x00000000005FE000-memory.dmp

        memory/220-20-0x0000000000400000-0x00000000005FE000-memory.dmp

        memory/220-13-0x0000000000400000-0x00000000005FE000-memory.dmp

        memory/220-17-0x0000000000400000-0x00000000005FE000-memory.dmp

        memory/1560-45-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-43-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-22-0x0000000002400000-0x000000000260F000-memory.dmp

        memory/1560-16-0x0000000000810000-0x0000000000825000-memory.dmp

        memory/1560-33-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-47-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-12-0x0000000000810000-0x0000000000825000-memory.dmp

        memory/1560-18-0x0000000000810000-0x0000000000825000-memory.dmp

        memory/1560-55-0x0000000007400000-0x000000000780B000-memory.dmp

        memory/1560-24-0x0000000002400000-0x000000000260F000-memory.dmp

        memory/1560-56-0x00000000029D0000-0x00000000029D7000-memory.dmp

        memory/1560-52-0x0000000007400000-0x000000000780B000-memory.dmp

        memory/1560-51-0x0000000001BF0000-0x0000000001BF5000-memory.dmp

        memory/1560-48-0x0000000001BF0000-0x0000000001BF5000-memory.dmp

        memory/1560-46-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-25-0x0000000000D40000-0x0000000000D46000-memory.dmp

        memory/1560-44-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-29-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-42-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-41-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-40-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-39-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-38-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-37-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-36-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-35-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-34-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-32-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/1560-31-0x0000000001BE0000-0x0000000001BF0000-memory.dmp

        memory/2056-7-0x0000000000400000-0x00000000005FE000-memory.dmp

        memory/2056-1-0x0000000000700000-0x0000000000800000-memory.dmp

        memory/2056-2-0x0000000002340000-0x0000000002353000-memory.dmp

        memory/2056-3-0x0000000000400000-0x0000000000415000-memory.dmp

        memory/2056-9-0x0000000000400000-0x0000000000415000-memory.dmp

        memory/2056-8-0x0000000002340000-0x0000000002353000-memory.dmp