Node.js is a JavaScript runtime environment that helps develop scalable applications on the Web server and the network. However, due to their popularity, applications may be subject to various cybersecurity attacks such as brute force, Web applications, leakage of sensitive information, and configuration vulnerabilities. This study aims to identify and reduce vulnerabilities caused by the exposure of services or applications through logical network ports. We developed this project with JavaScript, merging the phases of Design Science with Scrum, focused on feedback and continuous improvement. We also use Express.js to handle HTTP requests and define routes, with a middleware implemented for security and stability, including an incoming traffic monitor that records the number of requests received per-IP address. Also, we implemented a Web service and scripts to configure and manage the firewall programmatically. We employ port scanning, denial of services, and prevention and mitigation measures, such as hardening the Linux firewall with default policies to block malicious traffic. The study revealed vulnerabilities in the Node.js service and provided solutions to prevent and mitigate these issues, contributing to cybersecurity by identifying specific threats in Node.js services.