Analysis

  • max time kernel
    145s
  • max time network
    151s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20221111-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20221111-enlocale:en-usos:windows10-2004-x64system
  • submitted
    07/01/2023, 10:52

General

  • Target
    file.exe
  • Size 318KB
  • Sample230107-mydntsdd28
  • SHA256 7e1be73cd8799880c1f5ba4bf13db110f0fc37478d634196ada0b0cfd288f5b5
  • 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.

  • Looks up external IP address via web service 1 IoCs

    Uses a legitimate IP lookup service to find the infected system's external IP.

  • 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:4708
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\ykftosvv\
      2⤵
        PID:2692
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\lxgutpyd.exe" C:\Windows\SysWOW64\ykftosvv\
        2⤵
          PID:3688
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create ykftosvv binPath= "C:\Windows\SysWOW64\ykftosvv\lxgutpyd.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:3380
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description ykftosvv "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:4688
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start ykftosvv
          2⤵
          • Launches sc.exe
          PID:5084
        • 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:2224
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 4708 -s 1036
          2⤵
          • Program crash
          PID:4608
      • C:\Windows\SysWOW64\ykftosvv\lxgutpyd.exe
        C:\Windows\SysWOW64\ykftosvv\lxgutpyd.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
        1⤵
        • Executes dropped EXE
        • Suspicious use of SetThreadContext
        • Suspicious use of WriteProcessMemory
        PID:2864
        • 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:3732
          • 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:4448
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 2864 -s 512
          2⤵
          • Program crash
          PID:2704
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -pss -s 436 -p 4708 -ip 4708
        1⤵
          PID:2116
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -pss -s 520 -p 2864 -ip 2864
          1⤵
            PID:3128

          Network

                MITRE ATT&CK Enterprise v6

                Replay Monitor

                Loading Replay Monitor...

                Downloads

                lxgutpyd.exe

                • Path C:\Users\Admin\AppData\Local\Temp\lxgutpyd.exe
                • Size 10.5MB
                • SHA256 3cc0a8fc78441d08ad89ed5638094777dd08a2142fcbd8901a7eae104cdea817
                • MD5 SHA1 SHA512 SSDEEP

                lxgutpyd.exe

                • Path C:\Windows\SysWOW64\ykftosvv\lxgutpyd.exe
                • Size 10.5MB
                • SHA256 3cc0a8fc78441d08ad89ed5638094777dd08a2142fcbd8901a7eae104cdea817
                • MD5 SHA1 SHA512 SSDEEP

                memory/2864-150-0x0000000000400000-0x0000000003013000-memory.dmp

                memory/2864-148-0x0000000003299000-0x00000000032AE000-memory.dmp

                memory/3732-151-0x0000000000380000-0x0000000000395000-memory.dmp

                memory/3732-167-0x00000000025E0000-0x00000000025E7000-memory.dmp

                memory/3732-164-0x0000000007140000-0x000000000754B000-memory.dmp

                memory/3732-161-0x00000000025D0000-0x00000000025D5000-memory.dmp

                memory/3732-145-0x0000000000380000-0x0000000000395000-memory.dmp

                memory/3732-158-0x0000000002420000-0x0000000002430000-memory.dmp

                memory/3732-149-0x0000000000380000-0x0000000000395000-memory.dmp

                memory/3732-155-0x0000000002410000-0x0000000002416000-memory.dmp

                memory/3732-152-0x0000000002200000-0x000000000240F000-memory.dmp

                memory/4448-171-0x0000000000E00000-0x0000000000EF1000-memory.dmp

                memory/4448-176-0x0000000000E00000-0x0000000000EF1000-memory.dmp

                memory/4708-133-0x0000000004C20000-0x0000000004C33000-memory.dmp

                memory/4708-135-0x0000000000400000-0x0000000003013000-memory.dmp

                memory/4708-132-0x000000000319D000-0x00000000031B3000-memory.dmp

                memory/4708-143-0x0000000000400000-0x0000000003013000-memory.dmp