Analysis

  • max time kernel
    94s
  • max time network
    121s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20240412-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20240412-enlocale:en-usos:windows10-2004-x64system
  • submitted
    17/04/2024, 13:32

General

  • Target
    f6c76564b0268b7c3b754b05e498fcbc7e11fc1907460d12b1d55dd0d0662834.exe
  • Size 291KB
  • Sample240417-qs3ybabc2s
  • SHA256 f6c76564b0268b7c3b754b05e498fcbc7e11fc1907460d12b1d55dd0d0662834
  • 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) 1 TTPs
  • Modifies Windows Firewall 2 TTPs 1 IoCs
  • Checks computer location settings 2 TTPs 1 IoCs

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

  • Executes dropped EXE 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).

  • Program crash 1 IoCs
  • Suspicious use of WriteProcessMemory 18 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\f6c76564b0268b7c3b754b05e498fcbc7e11fc1907460d12b1d55dd0d0662834.exe
    "C:\Users\Admin\AppData\Local\Temp\f6c76564b0268b7c3b754b05e498fcbc7e11fc1907460d12b1d55dd0d0662834.exe"
    1⤵
    • Checks computer location settings
    • Suspicious use of WriteProcessMemory
    PID:1824
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\sfviqwbj\
      2⤵
        PID:5768
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\ovcfuibl.exe" C:\Windows\SysWOW64\sfviqwbj\
        2⤵
          PID:3384
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create sfviqwbj binPath= "C:\Windows\SysWOW64\sfviqwbj\ovcfuibl.exe /d\"C:\Users\Admin\AppData\Local\Temp\f6c76564b0268b7c3b754b05e498fcbc7e11fc1907460d12b1d55dd0d0662834.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:2868
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description sfviqwbj "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:5016
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start sfviqwbj
          2⤵
          • Launches sc.exe
          PID:876
        • 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
          PID:2748
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 1824 -s 1284
          2⤵
          • Program crash
          PID:4140
      • C:\Windows\SysWOW64\sfviqwbj\ovcfuibl.exe
        C:\Windows\SysWOW64\sfviqwbj\ovcfuibl.exe /d"C:\Users\Admin\AppData\Local\Temp\f6c76564b0268b7c3b754b05e498fcbc7e11fc1907460d12b1d55dd0d0662834.exe"
        1⤵
        • Executes dropped EXE
        PID:3232
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -pss -s 472 -p 1824 -ip 1824
        1⤵
          PID:5468

        Network

              MITRE ATT&CK Enterprise v15

              Replay Monitor

              Loading Replay Monitor...

              Downloads

              ovcfuibl.exe

              • Path C:\Users\Admin\AppData\Local\Temp\ovcfuibl.exe
              • Size 12.3MB
              • SHA256 c35cbd078f9f0dd931db314cf1f7d68c9ec506af08f4782c409a0baedc36f1c7
              • MD5 SHA1 SHA512 SSDEEP

              memory/1824-1-0x0000000002D90000-0x0000000002E90000-memory.dmp

              memory/1824-2-0x0000000002D60000-0x0000000002D73000-memory.dmp

              memory/1824-4-0x0000000000400000-0x0000000002ABF000-memory.dmp

              memory/1824-7-0x0000000000400000-0x0000000002ABF000-memory.dmp

              memory/1824-8-0x0000000002D60000-0x0000000002D73000-memory.dmp