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I have heard myths about how easy it is to crack a VBA macro password, but haven't been able to figure out how to do it myself. We have an excel file at work where the VBA is password protected and the developer has left and forgot the password. How do I get in?

1 Answer 1

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I have found this way:

  1. Open the file(s) that contain your locked VBA Projects

  2. Create a new xlsm file and store this code in Module1

Option Explicit

Private Const PAGE_EXECUTE_READWRITE = &H40

Private Declare Sub MoveMemory Lib "kernel32" Alias "RtlMoveMemory" _
        (Destination As Long, Source As Long, ByVal Length As Long)

Private Declare Function VirtualProtect Lib "kernel32" (lpAddress As Long, _
        ByVal dwSize As Long, ByVal flNewProtect As Long, lpflOldProtect As Long) As Long

Private Declare Function GetModuleHandleA Lib "kernel32" (ByVal lpModuleName As String) As Long

Private Declare Function GetProcAddress Lib "kernel32" (ByVal hModule As Long, _
        ByVal lpProcName As String) As Long

Private Declare Function DialogBoxParam Lib "user32" Alias "DialogBoxParamA" (ByVal hInstance As Long, _
        ByVal pTemplateName As Long, ByVal hWndParent As Long, _
        ByVal lpDialogFunc As Long, ByVal dwInitParam As Long) As Integer

Dim HookBytes(0 To 5) As Byte
Dim OriginBytes(0 To 5) As Byte
Dim pFunc As Long
Dim Flag As Boolean

Private Function GetPtr(ByVal Value As Long) As Long
    GetPtr = Value
End Function

Public Sub RecoverBytes()
    If Flag Then MoveMemory ByVal pFunc, ByVal VarPtr(OriginBytes(0)), 6
End Sub

Public Function Hook() As Boolean
    Dim TmpBytes(0 To 5) As Byte
    Dim p As Long
    Dim OriginProtect As Long

    Hook = False

    pFunc = GetProcAddress(GetModuleHandleA("user32.dll"), "DialogBoxParamA")

    If VirtualProtect(ByVal pFunc, 6, PAGE_EXECUTE_READWRITE, OriginProtect) <> 0 Then

        MoveMemory ByVal VarPtr(TmpBytes(0)), ByVal pFunc, 6
        If TmpBytes(0) <> &H68 Then

            MoveMemory ByVal VarPtr(OriginBytes(0)), ByVal pFunc, 6

            p = GetPtr(AddressOf MyDialogBoxParam)

            HookBytes(0) = &H68
            MoveMemory ByVal VarPtr(HookBytes(1)), ByVal VarPtr(p), 4
            HookBytes(5) = &HC3

            MoveMemory ByVal pFunc, ByVal VarPtr(HookBytes(0)), 6
            Flag = True
            Hook = True
        End If
    End If
End Function

Private Function MyDialogBoxParam(ByVal hInstance As Long, _
        ByVal pTemplateName As Long, ByVal hWndParent As Long, _
        ByVal lpDialogFunc As Long, ByVal dwInitParam As Long) As Integer
    If pTemplateName = 4070 Then
        MyDialogBoxParam = 1
    Else
        RecoverBytes
        MyDialogBoxParam = DialogBoxParam(hInstance, pTemplateName, _
                           hWndParent, lpDialogFunc, dwInitParam)
        Hook
    End If
End Function
  1. Paste this code in Module2 and run it
  Sub unprotected()
       If Hook Then
           MsgBox "VBA Project is unprotected!", vbInformation, "*****"
       End If
   End Sub
  1. Come back to your VBA Projects and enjoy.

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