Analysis

  • max time kernel
    148s
  • max time network
    152s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20220812-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20220812-enlocale:en-usos:windows10-2004-x64system
  • submitted
    07/01/2023, 01:42

General

  • Target
    file.exe
  • Size 300KB
  • Sample230107-b4nv7sce37
  • SHA256 47df2d80e3eafa936c8f6956e5ccbad7218a39fd24905a8d366b6e816d8fd7af
  • MD5 SHA1 SHA512 SSDEEP

Malware Config

Extracted

Family
  • tofsee

C2
  • svartalfheim.top

  • jotunheim.name

Signatures

  • Tofsee

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

  • xmrig

    XMRig is a high performance, open source, cross platform CPU/GPU miner.

  • XMRig Miner payload 2 IoCs
  • Creates new service(s) 1 TTPs
  • Executes dropped EXE 1 IoCs
  • 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.

  • Drops file in System32 directory 2 IoCs
  • Suspicious use of SetThreadContext 2 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). Likely ransomware behaviour.

  • Program crash 2 IoCs
  • Modifies data under HKEY_USERS 7 IoCs
  • Suspicious use of AdjustPrivilegeToken 1 IoCs
  • Suspicious use of WriteProcessMemory 28 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\file.exe
    "C:\Users\Admin\AppData\Local\Temp\file.exe"
    1⤵
    • Checks computer location settings
    • Suspicious use of WriteProcessMemory
    PID:1960
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\uzenbfvn\
      2⤵
        PID:4744
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\mfckbuol.exe" C:\Windows\SysWOW64\uzenbfvn\
        2⤵
          PID:2096
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create uzenbfvn binPath= "C:\Windows\SysWOW64\uzenbfvn\mfckbuol.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:3060
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description uzenbfvn "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:4376
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start uzenbfvn
          2⤵
          • Launches sc.exe
          PID:4304
        • 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:4772
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 1960 -s 1044
          2⤵
          • Program crash
          PID:3444
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -pss -s 456 -p 1960 -ip 1960
        1⤵
          PID:8
        • C:\Windows\SysWOW64\uzenbfvn\mfckbuol.exe
          C:\Windows\SysWOW64\uzenbfvn\mfckbuol.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
          1⤵
          • Executes dropped EXE
          • Suspicious use of SetThreadContext
          • Suspicious use of WriteProcessMemory
          PID:3524
          • C:\Windows\SysWOW64\svchost.exe
            svchost.exe
            2⤵
            • Sets service image path in registry
            • Drops file in System32 directory
            • Suspicious use of SetThreadContext
            • Modifies data under HKEY_USERS
            • Suspicious use of WriteProcessMemory
            PID:2176
            • C:\Windows\SysWOW64\svchost.exe
              svchost.exe -o fastpool.xyz:10060 -u 9mLwUkiK8Yp89zQQYodWKN29jVVVz1cWDFZctWxge16Zi3TpHnSBnnVcCDhSRXdesnMBdVjtDwh1N71KD9z37EzgKSM1tmS.60000 -p x -k -a cn/half
              3⤵
              • Suspicious use of AdjustPrivilegeToken
              PID:1460
          • C:\Windows\SysWOW64\WerFault.exe
            C:\Windows\SysWOW64\WerFault.exe -u -p 3524 -s 508
            2⤵
            • Program crash
            PID:2304
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -pss -s 532 -p 3524 -ip 3524
          1⤵
            PID:1504

          Network

                MITRE ATT&CK Enterprise v6

                Replay Monitor

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                Downloads

                mfckbuol.exe

                • Path C:\Users\Admin\AppData\Local\Temp\mfckbuol.exe
                • Size 13.2MB
                • SHA256 b98b7f490db768a50650ec929088efbc56a1ec505e4e78a96aeee97e65d6ffe9
                • MD5 SHA1 SHA512 SSDEEP

                mfckbuol.exe

                • Path C:\Windows\SysWOW64\uzenbfvn\mfckbuol.exe
                • Size 13.2MB
                • SHA256 b98b7f490db768a50650ec929088efbc56a1ec505e4e78a96aeee97e65d6ffe9
                • MD5 SHA1 SHA512 SSDEEP

                memory/1460-178-0x0000000000600000-0x00000000006F1000-memory.dmp

                memory/1460-173-0x0000000000600000-0x00000000006F1000-memory.dmp

                memory/1960-144-0x0000000002D90000-0x0000000002DA3000-memory.dmp

                memory/1960-133-0x0000000002D90000-0x0000000002DA3000-memory.dmp

                memory/1960-135-0x0000000000400000-0x0000000002C3D000-memory.dmp

                memory/1960-132-0x0000000002E1D000-0x0000000002E33000-memory.dmp

                memory/1960-145-0x0000000000400000-0x0000000002C3D000-memory.dmp

                memory/1960-143-0x0000000002E1D000-0x0000000002E33000-memory.dmp

                memory/2176-157-0x00000000005F0000-0x00000000005F6000-memory.dmp

                memory/2176-163-0x00000000017D0000-0x00000000017D5000-memory.dmp

                memory/2176-147-0x00000000001E0000-0x00000000001F5000-memory.dmp

                memory/2176-169-0x00000000017E0000-0x00000000017E7000-memory.dmp

                memory/2176-152-0x00000000001E0000-0x00000000001F5000-memory.dmp

                memory/2176-153-0x00000000001E0000-0x00000000001F5000-memory.dmp

                memory/2176-154-0x0000000002000000-0x000000000220F000-memory.dmp

                memory/2176-166-0x0000000007100000-0x000000000750B000-memory.dmp

                memory/2176-160-0x0000000001760000-0x0000000001770000-memory.dmp

                memory/3524-151-0x0000000000400000-0x0000000002C3D000-memory.dmp

                memory/3524-150-0x0000000002E19000-0x0000000002E2E000-memory.dmp