Skip to content

Instantly share code, notes, and snippets.

@vp777
Created May 14, 2019 21:02
Show Gist options
  • Save vp777/b9a9b1e1df70d45533c99d944df237d1 to your computer and use it in GitHub Desktop.
Save vp777/b9a9b1e1df70d45533c99d944df237d1 to your computer and use it in GitHub Desktop.
'Originally posted at: https://stackoverflow.com/questions/1026483/is-there-a-way-to-crack-the-password-on-an-excel-vba-project/53358962#53358962
'This version should work for both x86 and amd64 versions of Microsoft Office
Option Explicit
Private Const PAGE_EXECUTE_READWRITE = &H40
Private Declare PtrSafe Sub MoveMemory Lib "kernel32" Alias "RtlMoveMemory" _
(Destination As LongPtr, Source As LongPtr, ByVal Length As LongPtr)
Private Declare PtrSafe Function VirtualProtect Lib "kernel32" (lpAddress As LongPtr, _
ByVal dwSize As LongPtr, ByVal flNewProtect As LongPtr, lpflOldProtect As LongPtr) As LongPtr
Private Declare PtrSafe Function GetModuleHandleA Lib "kernel32" (ByVal lpModuleName As String) As LongPtr
Private Declare PtrSafe Function GetProcAddress Lib "kernel32" (ByVal hModule As LongPtr, _
ByVal lpProcName As String) As LongPtr
Private Declare PtrSafe Function DialogBoxParam Lib "user32" Alias "DialogBoxParamA" (ByVal hInstance As LongPtr, _
ByVal pTemplateName As LongPtr, ByVal hWndParent As LongPtr, _
ByVal lpDialogFunc As LongPtr, ByVal dwInitParam As LongPtr) As Integer
Dim HookBytes(0 To 11) As Byte
Dim OriginBytes(0 To 11) As Byte
Dim pFunc As LongPtr
Dim Flag As Boolean
Private Function GetPtr(ByVal Value As LongPtr) As LongPtr
GetPtr = Value
End Function
Public Sub RecoverBytes()
If Flag Then MoveMemory ByVal pFunc, ByVal VarPtr(OriginBytes(0)), 12
End Sub
Public Function Hook() As Boolean
Dim TmpBytes(0 To 11) As Byte
Dim p As LongPtr, osi As Byte
Dim OriginProtect As LongPtr
Hook = False
#If Win64 Then
osi = 1
#Else
osi = 0
#End If
pFunc = GetProcAddress(GetModuleHandleA("user32.dll"), "DialogBoxParamA")
If VirtualProtect(ByVal pFunc, 12, PAGE_EXECUTE_READWRITE, OriginProtect) <> 0 Then
MoveMemory ByVal VarPtr(TmpBytes(0)), ByVal pFunc, osi+1
If TmpBytes(osi) <> &HB8 Then
MoveMemory ByVal VarPtr(OriginBytes(0)), ByVal pFunc, 12
p = GetPtr(AddressOf MyDialogBoxParam)
If osi Then HookBytes(0) = &H48
HookBytes(osi) = &HB8
osi = osi + 1
MoveMemory ByVal VarPtr(HookBytes(osi)), ByVal VarPtr(p), 4 * osi
HookBytes(osi + 4 * osi) = &HFF
HookBytes(osi + 4 * osi + 1) = &HE0
MoveMemory ByVal pFunc, ByVal VarPtr(HookBytes(0)), 12
Flag = True
Hook = True
End If
End If
End Function
Private Function MyDialogBoxParam(ByVal hInstance As LongPtr, _
ByVal pTemplateName As LongPtr, ByVal hWndParent As LongPtr, _
ByVal lpDialogFunc As LongPtr, ByVal dwInitParam As LongPtr) As Integer
If pTemplateName = 4070 Then
MyDialogBoxParam = 1
Else
RecoverBytes
MyDialogBoxParam = DialogBoxParam(hInstance, pTemplateName, _
hWndParent, lpDialogFunc, dwInitParam)
Hook
End If
End Function
Sub unprotected()
If Hook Then
MsgBox "VBA Project is unprotected!", vbInformation, "*****"
End If
End Sub
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment