Analysis

  • max time kernel
    149s
  • max time network
    154s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20230915-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20230915-enlocale:en-usos:windows10-2004-x64system
  • submitted
    07/10/2023, 21:20

General

  • Target

    file.exe

  • Size

    287KB

  • MD5

    e2dc486d4a3d5af5052eb236ff0c3d80

  • SHA1

    7383776bf2a64bd5d1c99b116ffec759ab319834

  • SHA256

    400e730d88a031976f29527edf487159a4fd50702c657a2517678c70cdd1b7ac

  • SHA512

    36fee4138e59182b59edaf8138f590fc254280a0f4034fe949d0b6d94aed1ba968f475958dfbc234bf4ec5c83a936b47546c837664ec03b2a98f033038e4025d

  • SSDEEP

    3072:Cau1HZyD1WCagoqNJxaEx0lBJPMLnsmACWL+kbzjaa7OIp4Z:Ju10WJVqXxR0lBJUDsm7UTbnaKZp

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
  • 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 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 6 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:1760
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\xyuyniyw\
      2⤵
        PID:3016
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\rdpurxwk.exe" C:\Windows\SysWOW64\xyuyniyw\
        2⤵
          PID:1948
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create xyuyniyw binPath= "C:\Windows\SysWOW64\xyuyniyw\rdpurxwk.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:3236
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description xyuyniyw "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:844
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start xyuyniyw
          2⤵
          • Launches sc.exe
          PID:4764
        • 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:3844
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 1760 -s 660
          2⤵
          • Program crash
          PID:4716
      • C:\Windows\SysWOW64\xyuyniyw\rdpurxwk.exe
        C:\Windows\SysWOW64\xyuyniyw\rdpurxwk.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
        1⤵
        • Executes dropped EXE
        • Suspicious use of SetThreadContext
        • Suspicious use of WriteProcessMemory
        PID:780
        • 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:1256
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 780 -s 512
          2⤵
          • Program crash
          PID:1708
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -pss -s 452 -p 1760 -ip 1760
        1⤵
          PID:456
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -pss -s 460 -p 780 -ip 780
          1⤵
            PID:4404

          Network

          MITRE ATT&CK Enterprise v15

          Replay Monitor

          Loading Replay Monitor...

          Downloads

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

            Filesize

            12.7MB

            MD5

            41eff082affb2c2089fd7ffe3c0f4fae

            SHA1

            dde3b996146af08ea7d205223e7f497f1b81e7ee

            SHA256

            bdbccc5b23484e65107a1cb03bbda779896b52201afc4596f2a67b85d9075a75

            SHA512

            a007f3bcd924eda722e1d25fb5eb52271858350ea68a496c51705c0733b6eeb2293e3151912a4296e37baa61b44d131d475a53a1b5e08667f813d3dbca51c4bd

          • C:\Windows\SysWOW64\xyuyniyw\rdpurxwk.exe

            Filesize

            12.7MB

            MD5

            41eff082affb2c2089fd7ffe3c0f4fae

            SHA1

            dde3b996146af08ea7d205223e7f497f1b81e7ee

            SHA256

            bdbccc5b23484e65107a1cb03bbda779896b52201afc4596f2a67b85d9075a75

            SHA512

            a007f3bcd924eda722e1d25fb5eb52271858350ea68a496c51705c0733b6eeb2293e3151912a4296e37baa61b44d131d475a53a1b5e08667f813d3dbca51c4bd

          • memory/780-10-0x0000000002610000-0x0000000002710000-memory.dmp

            Filesize

            1024KB

          • memory/780-16-0x0000000000400000-0x0000000002284000-memory.dmp

            Filesize

            30.5MB

          • memory/780-15-0x0000000000400000-0x0000000002284000-memory.dmp

            Filesize

            30.5MB

          • memory/1256-33-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-35-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-56-0x00000000025E0000-0x00000000025E7000-memory.dmp

            Filesize

            28KB

          • memory/1256-11-0x0000000000160000-0x0000000000175000-memory.dmp

            Filesize

            84KB

          • memory/1256-14-0x0000000000160000-0x0000000000175000-memory.dmp

            Filesize

            84KB

          • memory/1256-55-0x0000000006F40000-0x000000000734B000-memory.dmp

            Filesize

            4.0MB

          • memory/1256-18-0x0000000000160000-0x0000000000175000-memory.dmp

            Filesize

            84KB

          • memory/1256-52-0x0000000006F40000-0x000000000734B000-memory.dmp

            Filesize

            4.0MB

          • memory/1256-20-0x0000000000160000-0x0000000000175000-memory.dmp

            Filesize

            84KB

          • memory/1256-21-0x0000000002000000-0x000000000220F000-memory.dmp

            Filesize

            2.1MB

          • memory/1256-24-0x0000000002000000-0x000000000220F000-memory.dmp

            Filesize

            2.1MB

          • memory/1256-25-0x0000000001720000-0x0000000001726000-memory.dmp

            Filesize

            24KB

          • memory/1256-28-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-31-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-32-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-51-0x00000000025D0000-0x00000000025D5000-memory.dmp

            Filesize

            20KB

          • memory/1256-34-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-48-0x00000000025D0000-0x00000000025D5000-memory.dmp

            Filesize

            20KB

          • memory/1256-37-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-36-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-38-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-39-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-40-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-41-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-42-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-43-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-44-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-45-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-46-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1256-47-0x0000000001730000-0x0000000001740000-memory.dmp

            Filesize

            64KB

          • memory/1760-8-0x00000000023F0000-0x0000000002403000-memory.dmp

            Filesize

            76KB

          • memory/1760-1-0x0000000002470000-0x0000000002570000-memory.dmp

            Filesize

            1024KB

          • memory/1760-2-0x00000000023F0000-0x0000000002403000-memory.dmp

            Filesize

            76KB

          • memory/1760-4-0x0000000000400000-0x0000000002284000-memory.dmp

            Filesize

            30.5MB

          • memory/1760-7-0x0000000000400000-0x0000000002284000-memory.dmp

            Filesize

            30.5MB