Analysis

  • max time kernel
    148s
  • max time network
    155s
  • 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, 13:00

General

  • Target
    f379c2c732470dbce8e17423baf7f6fcca63bcb13c4ade33a15df1225e3841be.exe
  • Size 232KB
  • Sample240417-p8metsgc76
  • SHA256 f379c2c732470dbce8e17423baf7f6fcca63bcb13c4ade33a15df1225e3841be
  • MD5 SHA1 SHA512 SSDEEP

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 6 IoCs
  • Suspicious use of WriteProcessMemory 23 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\f379c2c732470dbce8e17423baf7f6fcca63bcb13c4ade33a15df1225e3841be.exe
    "C:\Users\Admin\AppData\Local\Temp\f379c2c732470dbce8e17423baf7f6fcca63bcb13c4ade33a15df1225e3841be.exe"
    1⤵
    • Checks computer location settings
    • Suspicious use of WriteProcessMemory
    PID:4020
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\zkfjoolo\
      2⤵
        PID:2416
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\jsyjhwo.exe" C:\Windows\SysWOW64\zkfjoolo\
        2⤵
          PID:3052
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create zkfjoolo binPath= "C:\Windows\SysWOW64\zkfjoolo\jsyjhwo.exe /d\"C:\Users\Admin\AppData\Local\Temp\f379c2c732470dbce8e17423baf7f6fcca63bcb13c4ade33a15df1225e3841be.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:4312
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description zkfjoolo "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:3104
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start zkfjoolo
          2⤵
          • Launches sc.exe
          PID:4800
        • 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:880
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 4020 -s 656
          2⤵
          • Program crash
          PID:2172
      • C:\Windows\SysWOW64\zkfjoolo\jsyjhwo.exe
        C:\Windows\SysWOW64\zkfjoolo\jsyjhwo.exe /d"C:\Users\Admin\AppData\Local\Temp\f379c2c732470dbce8e17423baf7f6fcca63bcb13c4ade33a15df1225e3841be.exe"
        1⤵
        • Executes dropped EXE
        • Suspicious use of SetThreadContext
        • Suspicious use of WriteProcessMemory
        PID:2216
        • 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:2968
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 2216 -s 560
          2⤵
          • Program crash
          PID:4032
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -pss -s 468 -p 2216 -ip 2216
        1⤵
          PID:1000
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -pss -s 436 -p 4020 -ip 4020
          1⤵
            PID:4948

          Network

                MITRE ATT&CK Enterprise v15

                Replay Monitor

                Loading Replay Monitor...

                Downloads

                jsyjhwo.exe

                • Path C:\Users\Admin\AppData\Local\Temp\jsyjhwo.exe
                • Size 13.4MB
                • SHA256 ae05d0b24f690daa81ec57dd00fbe3b260089795229f580ff8a4da15bcb655e8
                • MD5 SHA1 SHA512 SSDEEP

                memory/2216-9-0x00000000005A0000-0x00000000005B3000-memory.dmp

                memory/2216-15-0x0000000000400000-0x000000000043F000-memory.dmp

                memory/2216-10-0x0000000000400000-0x000000000043F000-memory.dmp

                memory/2216-8-0x0000000000630000-0x0000000000730000-memory.dmp

                memory/2968-43-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-35-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-11-0x00000000007E0000-0x00000000007F5000-memory.dmp

                memory/2968-14-0x00000000007E0000-0x00000000007F5000-memory.dmp

                memory/2968-59-0x00000000007E0000-0x00000000007F5000-memory.dmp

                memory/2968-55-0x0000000002BD0000-0x0000000002BD7000-memory.dmp

                memory/2968-17-0x00000000007E0000-0x00000000007F5000-memory.dmp

                memory/2968-18-0x00000000007E0000-0x00000000007F5000-memory.dmp

                memory/2968-20-0x0000000002600000-0x000000000280F000-memory.dmp

                memory/2968-23-0x0000000002600000-0x000000000280F000-memory.dmp

                memory/2968-24-0x0000000000BF0000-0x0000000000BF6000-memory.dmp

                memory/2968-27-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-30-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-31-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-32-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-33-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-34-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-54-0x0000000007600000-0x0000000007A0B000-memory.dmp

                memory/2968-36-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-37-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-38-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-39-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-40-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-42-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-41-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-51-0x0000000007600000-0x0000000007A0B000-memory.dmp

                memory/2968-44-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-45-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-46-0x0000000001DA0000-0x0000000001DB0000-memory.dmp

                memory/2968-47-0x0000000001DF0000-0x0000000001DF5000-memory.dmp

                memory/2968-50-0x0000000001DF0000-0x0000000001DF5000-memory.dmp

                memory/4020-1-0x0000000000450000-0x0000000000550000-memory.dmp

                memory/4020-3-0x0000000000400000-0x000000000043F000-memory.dmp

                memory/4020-16-0x0000000000400000-0x000000000043F000-memory.dmp

                memory/4020-2-0x0000000002040000-0x0000000002053000-memory.dmp