Analysis

  • max time kernel
    149s
  • max time network
    143s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20230220-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20230220-enlocale:en-usos:windows10-2004-x64system
  • submitted
    17-05-2023 05:55

General

  • Target

    file.exe

  • Size

    233KB

  • MD5

    b76e2d8db8266762c770fbf801b33917

  • SHA1

    f8a8d5ced370552210f2b449ec2822c48e470bac

  • SHA256

    54f74659a4f85bab878e448b3ae96242c24f98f054cd7a16ce2a6b6daae4a70e

  • SHA512

    55b1de5e83d1f2cb7840b2eee2ac40dfcb0c1d289568b63a41e4b459f5fbb599c934df2805c1dd9b2b344133a39d4c2950997796605624ffff4dac1b32d7f76b

  • SSDEEP

    3072:EpqwYirEGOie1jXG7NlKAwQgbzRKr+6g3SVdwMByxMKiY54mYidF5Fkn:fwkGOCKbQIKL8vChm4m

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.

  • Executes dropped EXE 1 IoCs
  • Drops file in System32 directory 1 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 2 IoCs
  • Suspicious use of WriteProcessMemory 23 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:3340
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\dmrxxurt\
      2⤵
        PID:2576
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\coerfewa.exe" C:\Windows\SysWOW64\dmrxxurt\
        2⤵
          PID:2152
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create dmrxxurt binPath= "C:\Windows\SysWOW64\dmrxxurt\coerfewa.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:4716
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description dmrxxurt "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:4508
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start dmrxxurt
          2⤵
          • Launches sc.exe
          PID:3988
        • 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:1668
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 3340 -s 1172
          2⤵
          • Program crash
          PID:2716
      • C:\Windows\SysWOW64\dmrxxurt\coerfewa.exe
        C:\Windows\SysWOW64\dmrxxurt\coerfewa.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
        1⤵
        • Executes dropped EXE
        • Suspicious use of SetThreadContext
        • Suspicious use of WriteProcessMemory
        PID:4156
        • C:\Windows\SysWOW64\svchost.exe
          svchost.exe
          2⤵
          • Sets service image path in registry
          • Drops file in System32 directory
          • Modifies data under HKEY_USERS
          PID:4848
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 4156 -s 508
          2⤵
          • Program crash
          PID:5068
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -pss -s 480 -p 3340 -ip 3340
        1⤵
          PID:3144
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -pss -s 532 -p 4156 -ip 4156
          1⤵
            PID:4116

          Network

          MITRE ATT&CK Enterprise v6

          Replay Monitor

          Loading Replay Monitor...

          Downloads

          • C:\Users\Admin\AppData\Local\Temp\coerfewa.exe

            Filesize

            13.8MB

            MD5

            589a96469db9f9c051a82a10a586c7ea

            SHA1

            c805f17d498dc6a9ee315e44b9760cf936054664

            SHA256

            65d6ed315a62a55864e8865753448c6ba90e0e6d57a0c635561169ed8044e87b

            SHA512

            4b8725b29f2c98ad7e10bc91f0143fb945bd718cc4d4fce6da961994c59b4637991b48c1e66ba881dfd88ce90d9c1377d5f0ed1bf4c894aca8b8b0e8db9d1187

          • C:\Windows\SysWOW64\dmrxxurt\coerfewa.exe

            Filesize

            13.8MB

            MD5

            589a96469db9f9c051a82a10a586c7ea

            SHA1

            c805f17d498dc6a9ee315e44b9760cf936054664

            SHA256

            65d6ed315a62a55864e8865753448c6ba90e0e6d57a0c635561169ed8044e87b

            SHA512

            4b8725b29f2c98ad7e10bc91f0143fb945bd718cc4d4fce6da961994c59b4637991b48c1e66ba881dfd88ce90d9c1377d5f0ed1bf4c894aca8b8b0e8db9d1187

          • memory/3340-135-0x0000000000810000-0x0000000000823000-memory.dmp

            Filesize

            76KB

          • memory/3340-138-0x0000000000400000-0x00000000006B8000-memory.dmp

            Filesize

            2.7MB

          • memory/4156-144-0x0000000000400000-0x00000000006B8000-memory.dmp

            Filesize

            2.7MB

          • memory/4848-140-0x0000000000C90000-0x0000000000CA5000-memory.dmp

            Filesize

            84KB

          • memory/4848-143-0x0000000000C90000-0x0000000000CA5000-memory.dmp

            Filesize

            84KB

          • memory/4848-145-0x0000000000C90000-0x0000000000CA5000-memory.dmp

            Filesize

            84KB

          • memory/4848-146-0x0000000000C90000-0x0000000000CA5000-memory.dmp

            Filesize

            84KB

          • memory/4848-148-0x0000000000C90000-0x0000000000CA5000-memory.dmp

            Filesize

            84KB