Node.js Security Risks & Solutions — Part 1

Nirmal Joshi
5 min readSep 26, 2022

When it comes to web or mobile app development, trusted open-source technologies have become a developer’s favorite first choice. However, security becomes a point of major concern when it comes to using such technologies.

In web app development, Node.js is undoubtedly the most popular “go-to” technology. Even though it is designed to be completely secure, you’ll do need the help of various 3rd party packages through NPM (Node Package Manager) — and…it’s no secret that the NPM ecosystem is vulnerable to security issues.

In this blog and the one after this — I am going to discuss Node,js’s security vulnerabilities, along with the best practices and tools that you can utilize to improve your web application’s security.

Do remember, the points I am going to discuss are not in any specific order of importance.

  1. Code Injection Attacks

This refers to any attack where the attacker or hacker injects the code in the system and is able to force the application to execute it. This can happen if your data is not from a trusted source or the code is poorly handled.

The most common form of this attack is SQL injection attacks where the attacker is able to execute SQL statements on your database by manipulating the input data from the front-end. Trust me, it’s not a good situation to be in!

You can avoid this by not blindly passing the parameters from the frontend to the database query. Try and validate or escape values provided by the user which will depend on the database you use and the way you want to do it. I recommend using libraries like mongoose and node-mysql which will help you in escaping automatically.

2. Cross-Site Scripting (XSS) attack

Similar to SQL Injection Attacks, XSS attacks or cross-site scripting attacks are those in which the attacker is able to manipulate your JavaScript code. The reason being the same — not validating user input data!

An attacker can use XSS to send a malicious script to the end-user.

The end-user’s browser has no way to identify the trustworthiness of the codebase & when they execute it — the attackers have a party by having access to any cookies, session tokens, or even sensitive information. Not only that, these scripts can also rewrite the content of any HTML page, making an XSS attack, a fatal blow to your precious code!

The best way to avoid this is pretty simple — validate the user input! You can use xss-filters or validatorjs for that.

3. Make strong authentication policies

Weak or inconsistent authentication is easy to bypass. So don’t think that you have authentication, so you’re secure. A broken, incomplete or weak authentication system is the root cause of majority security breaches.

The best way to tackle this is by building high-level and robust authentication policies for your web application. Execute a “two-factor” or even “multi-factor” authentication on your app to get rid of weak passwords. Try using ready-to-use solutions like OAuth, Okta or Firebase Auth. And remember, always prefer those solutions that follow strict security standards and have necessary certifications.

4. Error handling to prevent unauthorized attacks

Handling errors is very crucial for smooth functioning of your app! I always tell my students — “Don’t return the full error object to the client” — which essentially means don’t let the user know the details that you do not want to expose. It could be anything — a library in use, paths, some sensitive information that is lucrative to the attacker etc.

Also, don’t let Node.js crash when the error was triggered from a request. The moment attackers know the application’s vulnerability, they might send repeated requests which can cause the application to crash.

What can you do? Simply, wrap express routes with a catch clause to avoid displaying or leaking sensitive information. Don’t expose your Node.js app to others, use some component in front of it such as a cloud firewall or gateway, a load balancer, or even Ngnix can be used to limit DOS attacks.

5. Avoid data leakage by sending only necessary information

Another common problem that a developer has to face — Data leaks!

Sending all data for a particular object to the front-end and only filtering what to show there isn’t the right approach. For attackers, gaining access to hidden data sent from the backend is easier than before.

How can you solve this? Send specific data that is required. Yes, it will take a bit more time and energy but trust me, it will be worth it. I also recommend using various encryption techniques to encrypt all the essential data which will help in securing your data.

6. Avoid irregularities by keeping a watch on logging and monitoring

One can debate that this has nothing to do with security but believe me it does. Irregular logging and monitoring can cause major security vulnerabilities that have cost many companies a fortune in the past.

Basic logging won’t fetch enough information for you to understand if weird-looking requests are coming from your own application, a third-party API, or from a hacker. So, regular monitoring and logging activities is a must!

Node.js’s internal modules like Winston, Bunyan, and Pinto can be used to handle uncaught exceptions and querying logs.

Alright folks, these were a few important pointers on how you can avoid security threats for your Node.js app. The next blog will cover a few more such points.

About me:

Founder and CEO of an IT company in India, I have more than 25 years experience of in dealing with people, processes, and codes. I started online training for my students when it was not in fashion and have trained more than 1000 students/working professionals personally which has helped them to secure awesome jobs or even start their own businesses.

Check out my Udemy profile to know more about the courses that I teach.

I am also been an active corporate trainer for several years now and have been consulting with top Fortune 500/1000 companies to streamline their development projects efficiently. My goal is to share knowledge with a primary focus on advanced tools & techniques, projects, and standard programming practices to help my students understand the basics and fundamentals and make awesome technological implementations.



Nirmal Joshi

A founder and CEO of an IT company in India, I have more than 22+ years’ experience of dealing with people, processes and codes.