When you start to focus on the performance and security of your backend alongside the other features, you know that you're growing and maturing as a developer. It goes without saying but having some sort of security measure against common attacks is essential, even if it's just a hobby project.
If you're new to security or want to quickly get started with some basic protection, these 5 NPM packages will help you get started in just a few minutes. The best part about these packages is that all you have to do is just install them and use them as middleware. It's that easy!
In a hurry or just need the list of packages? Here are the 5 NPM packages that I'll be going over:
| Package Name | Package Link |
|---|---|
| helmet | NPM Link |
| xss-clean | NPM Link |
| hpp | NPM Link |
| express-mongo-sanitize | NPM Link |
| express-rate-limit | NPM Link |
Helmet
What it does: Sets security-related HTTP response headers to protect against some well-known web vulnerabilities.
What does it protect against: Cross-site scripting attacks, cross-site injections, clickjacking, MIME sniffing and targeted attacks towards Express servers by disabling the X-Powered-By header.
How to use it:
npm install helmet
const app = require('express')();
const helmet = require('helmet');
// Using helmet middleware
app.use(helmet());
app.listen(1337);
Helmet
Helmet helps secure Express apps by setting HTTP response headers.
Get started
Here's a sample Express app that uses Helmet:
import express from "express";
import helmet from "helmet";
const app = express();
// Use Helmet!
app.use(helmet());
app.get("/", (req, res) => {
res.send("Hello world!");
});
app.listen(8000);
You can also require("helmet") if you prefer.
By default, Helmet sets the following headers:
-
Content-Security-Policy: A powerful allow-list of what can happen on your page which mitigates many attacks -
Cross-Origin-Opener-Policy: Helps process-isolate your page -
Cross-Origin-Resource-Policy: Blocks others from loading your resources cross-origin -
Origin-Agent-Cluster: Changes process isolation to be origin-based -
Referrer-Policy: Controls theRefererheader -
Strict-Transport-Security: Tells browsers to prefer HTTPS -
X-Content-Type-Options: Avoids…
XSS-Clean
What it does: Sanitizes user input coming from POST request body (req.body), GET request query (req.query) and URL parameters (req.params).
What does it protect against: Cross-site scripting / XSS attacks.
How to use it:
npm install xss-clean
const app = require('express')();
const xssClean = require('xss-clean');
// Protect against XSS attacks, should come before any routes
app.use(xssClean());
app.listen(1337);
Announcement
This library has been deprecated. The implementation is quite simple, and I would suggest you copy the source code directly into your application using the xss-filters dependency, or look for alternative libraries with more features and attention. Thanks for your support.
Node.js Connect middleware to sanitize user input coming from POST body, GET queries, and url params. Works with Express, Restify, or any other Connect app.
How to Use
npm install xss-clean --save
const restify = require('restify')
const xss = require('xss-clean')
const app = restify.createServer()
app.use(restify.bodyParser())
// make sure this comes before any routes
app.use(xss())
app.listen(8080)
This will sanitize any data in req.body, req.query, and req.params. You can also…
HPP
What it does: Puts the array parameters in req.query and/or req.body asides and just selects the last parameter value to avoid HTTP Parameter Pollution attacks.
What does it protect against: Bypassing input validations and denial of service (DoS) attacks by uncaught TypeError in async code, leading to server crash.
How to use it:
npm install hpp
const app = require('express')();
const hpp = require('hpp');
// Protect against HPP, should come before any routes
app.use(hpp());
app.listen(1337);
analog-nico
/
hpp
Express middleware to protect against HTTP Parameter Pollution attacks
HPP
Express middleware to protect against HTTP Parameter Pollution attacks
Why?
Let Chetan Karande's slides do the explaining:
...and exploits may allow bypassing the input validation or even result in denial of service.
And HPP solves this how exactly?
HPP puts array parameters in req.query and/or req.body aside and just selects the last parameter value. You add the middleware and you are done.
Installation
This is a module for node.js and io.js and is installed via npm:
npm install hpp --save
Getting Started
Add the HPP middleware like this:
// ...
var hpp = require('hpp');
// ...
app.use(bodyParser.urlencoded()); // Make sure the body is parsed beforehand.
app.use(hpp()); // <- THIS IS THE NEW LINE
// Add your own middlewares afterwards, e.g.:
app.get('/search',…Express Mongo Sanitize
What it does: Searches for any keys in objects that begin with a $ sign or contain a . from req.body, req.query or req.params and either removes such keys and data or replaces the prohibited characters with another allowed character.
What does it protect against: MongoDB Operator Injection. Malicious users could send an object containing a $ operator, or including a ., which could change the context of a database operation.
How to use it:
npm install express-mongo-sanitize
const app = require('express')();
const mongoSanitize = require('express-mongo-sanitize');
// Remove all keys containing prohibited characters
app.use(mongoSanitize());
app.listen(1337);
fiznool
/
express-mongo-sanitize
Sanitize your express payload to prevent MongoDB operator injection.
Express Mongo Sanitize
Express 4.x middleware which sanitizes user-supplied data to prevent MongoDB Operator Injection.
What is this module for?
This module searches for any keys in objects that begin with a $ sign or contain a ., from req.body, req.query, req.headers or req.params. It can then either:
- completely remove these keys and associated data from the object, or
- replace the prohibited characters with another allowed character.
The behaviour is governed by the passed option, replaceWith. Set this option to have the sanitizer replace the prohibited characters with the character passed in.
The config option allowDots can be used to allow dots in the user-supplied data. In this case, only instances of $ will be sanitized.
See the spec file for more examples.
Why is it needed?
Object keys starting with a $ or containing a . are reserved for use by MongoDB as operators…
Express Rate Limit
What does it do: Used to limit IP addresses from making repeated requests to API endpoints. An example would be to rate limit an endpoint that is responsible for sending password reset emails, which can incur additional fees.
What does it protect against: Brute force, denial of service (DoS) and distributed denial of service (DDoS) attacks.
How to use it:
npm install express-rate-limit
const app = require('express')();
const rateLimit = require('express-rate-limit');
// Restrict all routes to only 100 requests per IP address every 1o minutes
const limiter = rateLimit({
windowMs: 10 * 60 * 1000, // 10 minutes
max: 100 // 100 requests per IP
});
app.use(limiter);
app.listen(1337);
express-rate-limit
/
express-rate-limit
Basic rate-limiting middleware for express
Express Rate Limit
Sponsored by Zuplo a fully-managed API Gateway for developers. Add dynamic rate-limiting authentication and more to any API in minutes. Learn more at zuplo.com
Basic rate-limiting middleware for Express. Use to limit repeated requests to public APIs and/or endpoints such as password reset. Plays nice with express-slow-down.
Alternate Rate Limiters
This module does not share state with other processes/servers by default. If you need a more robust solution, I recommend using an external store. See the
storessection below for a list of external stores.
This module was designed to only handle the basics and didn't even support external stores initially. These other options all are excellent pieces of software and may be more appropriate for some situations:
Installation
From the npm registry:
# Using npm
> npm install express-rate-limit
# Using yarn or pnpm
> yarn/pnpm add express-rate-limit
From Github Releases:
With these 5 NPM packages, you can make your Node.js + Express.js application much more secure in just 5 minutes. All of the packages above are extremely easy to use, just export and use as a middleware.
What security precautions do you take? Or did I miss any of your favorite packages? Let me know in the discussion below and I'll be happy to hear your thoughts.
Top comments (10)
Awesome article thank you…also side note love your VScode theme portfolio, so clever!
I'm a Web developer, and I recently took up a ethical hacking course to see how I can combine the knowledge to my expertise in web dev. And one thing which actually worried me was the Man in the middle attack. Good to see there is a way to prevent this. Thanks a ton for sharing this!!! Great job!
Oh wow, I'm really glad you found the article to be helpful. Could you link me to the course you're talking about, curious about the content. Thanks for reading!
Sure actually it's an internship course I'm doing, which I got after answering the exam NEO. It happens once in a year.
Thanks. This is concise and immediately usable. Well done.
Very helpful and educational article thanks Nitin!
Thank you so much for reading :)
I am using mongo as database for a while and I was worried about malicious data which can change my initial query , I think mongo sanitize will help me ... Thanks @itsnitinr for you article
I'm sure it will. Glad to have helped you out and thank you for reading.
node-rate-limiter-flexible is good for more specific rate limiting. You can rate limit by IP, user or IP and user.