Analysis

  • max time kernel
    158s
  • max time network
    167s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20231215-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20231215-enlocale:en-usos:windows10-2004-x64system
  • submitted
    12/01/2024, 10:51

General

  • Target
    8bcf8cc2c1f767e639cfd2de9ad3d548.exe
  • Size 288KB
  • Sample240112-mxtzesfcc7
  • SHA256 fd79a1b3b18fca2696c2c58f290a4dadb97e3cdcd6e98d14a63ac3f4a1f2e351
  • 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 1 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).

  • Program crash 2 IoCs
  • Modifies data under HKEY_USERS 7 IoCs
  • Suspicious use of WriteProcessMemory 23 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\8bcf8cc2c1f767e639cfd2de9ad3d548.exe
    "C:\Users\Admin\AppData\Local\Temp\8bcf8cc2c1f767e639cfd2de9ad3d548.exe"
    1⤵
    • Checks computer location settings
    • Suspicious use of WriteProcessMemory
    PID:4560
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\izwewlcf\
      2⤵
        PID:1836
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\zczsjlfv.exe" C:\Windows\SysWOW64\izwewlcf\
        2⤵
          PID:3252
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create izwewlcf binPath= "C:\Windows\SysWOW64\izwewlcf\zczsjlfv.exe /d\"C:\Users\Admin\AppData\Local\Temp\8bcf8cc2c1f767e639cfd2de9ad3d548.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:3756
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description izwewlcf "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:4188
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start izwewlcf
          2⤵
          • Launches sc.exe
          PID:4988
        • 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:2324
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 4560 -s 1192
          2⤵
          • Program crash
          PID:2796
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -pss -s 456 -p 4560 -ip 4560
        1⤵
          PID:3244
        • C:\Windows\SysWOW64\izwewlcf\zczsjlfv.exe
          C:\Windows\SysWOW64\izwewlcf\zczsjlfv.exe /d"C:\Users\Admin\AppData\Local\Temp\8bcf8cc2c1f767e639cfd2de9ad3d548.exe"
          1⤵
          • Executes dropped EXE
          • Suspicious use of SetThreadContext
          • Suspicious use of WriteProcessMemory
          PID:2444
          • C:\Windows\SysWOW64\svchost.exe
            svchost.exe
            2⤵
            • Sets service image path in registry
            • Deletes itself
            • Drops file in System32 directory
            • Modifies data under HKEY_USERS
            PID:3052
          • C:\Windows\SysWOW64\WerFault.exe
            C:\Windows\SysWOW64\WerFault.exe -u -p 2444 -s 532
            2⤵
            • Program crash
            PID:3312
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -pss -s 500 -p 2444 -ip 2444
          1⤵
            PID:412

          Network

                MITRE ATT&CK Enterprise v15

                Replay Monitor

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                Downloads

                zczsjlfv.exe

                • Path C:\Users\Admin\AppData\Local\Temp\zczsjlfv.exe
                • Size 11.9MB
                • SHA256 da9ec6d2b3cdc8e5e4dcdc10510cb98fd5c3a88d822bc18dec6487f94428b60c
                • MD5 SHA1 SHA512 SSDEEP

                memory/2444-18-0x0000000000400000-0x0000000000450000-memory.dmp

                memory/2444-13-0x0000000000400000-0x0000000000450000-memory.dmp

                memory/2444-12-0x0000000000770000-0x0000000000870000-memory.dmp

                memory/3052-35-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-36-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-62-0x0000000000AD0000-0x0000000000AE5000-memory.dmp

                memory/3052-58-0x0000000001FF0000-0x0000000001FF7000-memory.dmp

                memory/3052-57-0x0000000007700000-0x0000000007B0B000-memory.dmp

                memory/3052-54-0x0000000007700000-0x0000000007B0B000-memory.dmp

                memory/3052-14-0x0000000000AD0000-0x0000000000AE5000-memory.dmp

                memory/3052-17-0x0000000000AD0000-0x0000000000AE5000-memory.dmp

                memory/3052-53-0x0000000001FE0000-0x0000000001FE5000-memory.dmp

                memory/3052-39-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-21-0x0000000000AD0000-0x0000000000AE5000-memory.dmp

                memory/3052-23-0x0000000002800000-0x0000000002A0F000-memory.dmp

                memory/3052-26-0x0000000002800000-0x0000000002A0F000-memory.dmp

                memory/3052-27-0x0000000001F80000-0x0000000001F86000-memory.dmp

                memory/3052-30-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-33-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-50-0x0000000001FE0000-0x0000000001FE5000-memory.dmp

                memory/3052-34-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-49-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-37-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-20-0x0000000000AD0000-0x0000000000AE5000-memory.dmp

                memory/3052-38-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-40-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-41-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-42-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-43-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-44-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-45-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-46-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-47-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/3052-48-0x0000000001F90000-0x0000000001FA0000-memory.dmp

                memory/4560-7-0x0000000000400000-0x0000000000450000-memory.dmp

                memory/4560-1-0x00000000007A0000-0x00000000008A0000-memory.dmp

                memory/4560-2-0x00000000005A0000-0x00000000005B3000-memory.dmp

                memory/4560-3-0x0000000000400000-0x0000000000450000-memory.dmp

                memory/4560-5-0x0000000000400000-0x0000000000450000-memory.dmp

                memory/4560-11-0x00000000005A0000-0x00000000005B3000-memory.dmp

                memory/4560-8-0x00000000007A0000-0x00000000008A0000-memory.dmp