How do you make a real-time proccess MD5# scanner?

Quote:

Currently, I'm trying to build a program which scans all running processes, gets the MD5# of that process, and compares it to a .txt file which has a list of MD5 hashes.

Looks like a bad idea from the beginning.
Chances are that your reference MD5 will never match. The reason is that the executable disk file is never the same as the process.
Part of the loading process is to resolve internal and external jumps in code. The resolution of those jumps depend on loading address of the process and loading addresses of external code the process use.
Said otherwise, to get the same MD5 for a running process, it imply that the whole system have started exactly the same way both times. this include an exact same dynamic memory allocation for all previous processes.

Your text file should contain lines with the full path and the MD5 sum separated by a delimiting sequence. Read that file line by line and split each line into the path and MD5 sum part. If a file name matches (should be case insentive with Windows) return a state that indicates if the MD5 sum matches or not. When reaching the end of the file, return a state that the file has not been found.

Writing such code is a basic task in any programming language. Examples can be found by searching the web for something like "vb.net read text file line by line": File.ReadAllLines Method (String) (System.IO)[^]

Splitting a string into components is again a basic task. Each programming language provides functions to split strings at specific characters: String.Split Method (Char[]) (System)[^]

In your scenario you might also use a Dictionary(TKey, TValue) Class (System.Collections.Generic)[^] to perform the lookup. That can be created at program start from the text file or be loaded using serialisation when you have created a corresponding serialised file.

Private Sub Mainframe_Load(sender As Object, e As EventArgs) Handles MyBase.Load

       Dim procs() As System.Diagnostics.Process = System.Diagnostics.Process.GetProcesses
       Dim f As String

       For Each proc As System.Diagnostics.Process In procs
           f = GetProcessFileName(proc)
           If f.Length > 0 Then
               ListBox1.Items.Add(f)
               ListBox1.Items.Add("MD5: " & GetMD5String(f))
               ListBox1.Items.Add(String.Empty)
           End If

       Next

   End Sub

Private Function GetProcessFileName(proc As System.Diagnostics.Process) As String
       Dim strRet As String = String.Empty

       Try
           strRet = proc.MainModule.FileName
       Catch ex As Exception
           ' This catch used to ignore "Access is denied" exception.
       End Try
       Return strRet
   End Function

Private Function GetMD5String(ByVal strFilename As String) As String
       Dim cMD5 = System.Security.Cryptography.MD5.Create
       Dim bytHash As Byte()
       Dim sb As New System.Text.StringBuilder
       Dim scanbox As New TextBox
       scanbox.Text = My.Computer.FileSystem.ReadAllText("viruslist.txt").ToString

       Using cStream As New IO.FileStream(strFilename, IO.FileMode.Open, IO.FileAccess.Read, IO.FileShare.Read)

           bytHash = cMD5.ComputeHash(cStream)
       End Using

       For Each B In bytHash
           sb.Append(B.ToString("X2"))
       Next

       If scanbox.Text.Contains(sb.ToString) Then
           Detect.Show()
       End If

       Return sb.ToString



   End Function

"Doubt is a pain too lonely to know that faith is his twin brother."