Analysis

  • max time kernel
    147s
  • max time network
    152s
  • 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

    87dc843c26db143ec9d2869ee4be3e53593fa7b4331a0ceb170f6e2339caa304.exe

  • Size

    209KB

  • MD5

    33a5257b9ea7acdc82c83014bf5e10c4

  • SHA1

    55b35da44a67a5363f56921804defaa084a2265e

  • SHA256

    87dc843c26db143ec9d2869ee4be3e53593fa7b4331a0ceb170f6e2339caa304

  • SHA512

    1f64da365ca4bfe6934bc4681155d3597f61fef4a9338de16675ad3e7492174a800cdf98e2eb3537b39ebcb4040b05b433768e1d999e82b18779b7d2e139393e

  • SSDEEP

    3072:dSSQtGlfg7lQJi9oFseTH0b5dkOExzi6EgdpRIDEqGA:YS/fg7lETzOERpdA

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
  • 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 3 IoCs
  • Suspicious use of WriteProcessMemory 23 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\87dc843c26db143ec9d2869ee4be3e53593fa7b4331a0ceb170f6e2339caa304.exe
    "C:\Users\Admin\AppData\Local\Temp\87dc843c26db143ec9d2869ee4be3e53593fa7b4331a0ceb170f6e2339caa304.exe"
    1⤵
    • Checks computer location settings
    • Suspicious use of WriteProcessMemory
    PID:1856
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\dhqfimoa\
      2⤵
        PID:2872
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\elkxffnr.exe" C:\Windows\SysWOW64\dhqfimoa\
        2⤵
          PID:404
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create dhqfimoa binPath= "C:\Windows\SysWOW64\dhqfimoa\elkxffnr.exe /d\"C:\Users\Admin\AppData\Local\Temp\87dc843c26db143ec9d2869ee4be3e53593fa7b4331a0ceb170f6e2339caa304.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:4900
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description dhqfimoa "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:1552
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start dhqfimoa
          2⤵
          • Launches sc.exe
          PID:4816
        • 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:4532
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 1856 -s 800
          2⤵
          • Program crash
          PID:4296
      • C:\Windows\SysWOW64\dhqfimoa\elkxffnr.exe
        C:\Windows\SysWOW64\dhqfimoa\elkxffnr.exe /d"C:\Users\Admin\AppData\Local\Temp\87dc843c26db143ec9d2869ee4be3e53593fa7b4331a0ceb170f6e2339caa304.exe"
        1⤵
        • Executes dropped EXE
        • Suspicious use of SetThreadContext
        • Suspicious use of WriteProcessMemory
        PID:3224
        • 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:3040
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 3224 -s 524
          2⤵
          • Program crash
          PID:4792
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -pss -s 460 -p 1856 -ip 1856
        1⤵
          PID:3288
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -pss -s 480 -p 3224 -ip 3224
          1⤵
            PID:3360

          Network

          MITRE ATT&CK Enterprise v15

          Replay Monitor

          Loading Replay Monitor...

          Downloads

          • C:\Users\Admin\AppData\Local\Temp\elkxffnr.exe
            Filesize

            10.7MB

            MD5

            b9042fcaee44be479ba4a626ca1f469b

            SHA1

            78bc3bb54a94ad865f0e46a82b26d285505f35f3

            SHA256

            4ad89f21a3bbdf38b82ea80a6272699c66f4ec86702d7c5c22cac7b54f989c7e

            SHA512

            d25bc7ee5deaa2ec811fa88e7987d52c01865b67616a40aac07b791138a2a49dcd11adcad82eb4cfa40e0f389a0bc43c1537f6ae13373a0f2b9e9d3e835c7c38

          • memory/1856-16-0x0000000000400000-0x000000000043A000-memory.dmp
            Filesize

            232KB

          • memory/1856-2-0x0000000000480000-0x0000000000493000-memory.dmp
            Filesize

            76KB

          • memory/1856-3-0x0000000000400000-0x000000000043A000-memory.dmp
            Filesize

            232KB

          • memory/1856-1-0x00000000004B0000-0x00000000005B0000-memory.dmp
            Filesize

            1024KB

          • memory/3040-20-0x0000000000E30000-0x0000000000E45000-memory.dmp
            Filesize

            84KB

          • memory/3040-18-0x0000000000E30000-0x0000000000E45000-memory.dmp
            Filesize

            84KB

          • memory/3040-9-0x0000000000E30000-0x0000000000E45000-memory.dmp
            Filesize

            84KB

          • memory/3040-14-0x0000000000E30000-0x0000000000E45000-memory.dmp
            Filesize

            84KB

          • memory/3040-17-0x0000000000E30000-0x0000000000E45000-memory.dmp
            Filesize

            84KB

          • memory/3224-11-0x0000000000400000-0x000000000043A000-memory.dmp
            Filesize

            232KB

          • memory/3224-15-0x0000000000400000-0x000000000043A000-memory.dmp
            Filesize

            232KB

          • memory/3224-10-0x00000000005B0000-0x00000000005C3000-memory.dmp
            Filesize

            76KB

          • memory/3224-8-0x00000000005E0000-0x00000000006E0000-memory.dmp
            Filesize

            1024KB