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React Security Vulnerabilities: How to Protect Your App and Fix Them

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React has become the most popular JavaScript (JS) framework, and it’s not hard to see why. It’s used by top companies like Facebook, Netflix, Airbnb, Uber, and many more!

If you’re new to React or are thinking about using it in your next project, there are some important security vulnerabilities that you must not overlook.

React Vulnerabilities provide developers with specific recommendations on how to prevent and fix these vulnerabilities, so you can avoid future issues and make your apps more secure.

If you’re using React, it’s important to understand these vulnerabilities and how to protect your app against them. In this article, we’ll explain what the React security vulnerabilities are, and we’ll show you how to fix them.

Why Choose ReactJS?

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What are security vulnerabilities?

In computer security, a vulnerability is a weakness that can be exploited by a threat actor. Vulnerabilities are often documented as bugs in software that allow attackers to make changes to your website or application.

These changes are typically malicious but may sometimes be used for good, such as exposing errors in security, design, or others. Knowing how vulnerabilities affect your site is an important step toward protecting it from external threats.

In general, there are two types of vulnerabilities on websites: client-side and server-side vulnerabilities. Security vulnerabilities are often discovered by white-hat hackers and reported to the affected company so they can be fixed.

In the context of web applications, security vulnerabilities can allow attackers to steal user data, inject malicious code into an app, or take control of a user’s account.

Moreover, in order to resolve React Vulnerabilities, you can hire React developers. This will not only help you in resolving the issues but will also help you in making your application error-free.

Some Common React Vulnerabilities and Its Solutions

There are several common security issues that you need to be aware of when you are running or building React applications:

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Cross-Site Scripting (XSS)

When code is injected into your website by an attacker, it’s referred to as cross-site scripting (XSS). The malicious code can change elements on your page, steal cookies or even delete data.

It’s also harder for automated security scanners to detect these types of issues. That makes XSS one of the most dangerous threats when building a React app.

One way to protect against XSS vulnerabilities is through strict escaping. This should be used with caution since browsers are supposed to automatically escape HTML content already. It can also degrade performance if used inappropriately, which could ruin your experience with React Native mobile apps.

Injection Attacks

An injection attack occurs when an attacker injects malicious code into an application. Hackers inject their malicious code via websites, social media platforms, etc.

Injection attacks have been known to allow hackers access through web pages that give them control over databases. Accessing databases gives hackers control over credit card information and other sensitive data for numerous applications.

It is advised that you always store your data offline in a secure server or database, especially if it includes sensitive information about users such as passwords or credit card numbers.

Using a dedicated server for storing your data would be ideal in order to prevent any unwanted breaches of security from occurring.

CSRF Attacks

Cross-Site Request Forgery (CSRF) is an attack that forces a logged-in user’s browser to send a forged HTTP request, without their knowledge, in order to execute a malicious action.

CSRF attacks specifically target state-changing requests (POST, PUT or DELETE) since those are considered more sensitive than “GET” requests.

The attacker lures a victim on another site by using anything from social engineering (like posting messages about kittens) all the way up to malware that can automatically trigger attacks for them. Of course, there are many other ways for attackers to access your users’ cookies without being on your network at all.

By limiting the number of requests that are vulnerable to CSRF attacks, you can protect yourself from malicious links on websites. The key design principle in this matter is using GET instead of other types like PUT or POST because these will transform data while being accessed by your browser, which makes them riskier forgery methods.

Malicious File Uploads

An attacker could easily upload malicious code to your server. By sending a form submission containing an image field, they could get you to execute that malicious code on your server.

This is easily prevented by ensuring that all uploads are validated. If you’re using something like Amazon S3, that service can help you prevent malicious file uploads by adding a simple check-in to their AWS IAM console (see below).

Alternately, if you’re hosting your own server, check out a module like Nodejs-Security-Shield, which allows you to do something similar.

Insufficient Authorization & Authentication

Authorization refers to who can access specific data, and authentication determines whether or not that person is who they say they are. A common vulnerability occurs when authorization checks aren’t performed on all methods used by an app.

For example, users may be required to log in before viewing their personal account details but not before viewing customer orders. In these cases, hackers can exploit these privileged methods (such as getting a list of all your customers) by simply passing an access token to another user (for example, a customer).

To mitigate these vulnerabilities in react apps, use JWT or JSON Web Tokens for authorization.

Distributed Denial of Service (DDoS)

This is a very common attack where a botnet (hundreds or thousands of compromised computers) is used to flood your server with traffic. The goal is to cause so much excess load that it takes down your app or website.

As one of the most straightforward attacks, you’ll want to make sure your app can handle large bursts of requests in order for it not to be taken down.

A good way to defend against DDoS attacks is through server-level request throttling — keeping track of how many simultaneous requests are being made at any given time, checking if they’re valid, and limiting them if they aren’t. This works especially well with services like Cloudflare, which offers additional security layers by default.

XML External Entity Attack (XXE)

When a web application processes XML data, it’s possible for an attacker to cause a DoS by exhausting system resources or consuming memory. The attack can be performed using maliciously crafted XML content from external sources outside of your server.

In order to prevent XXE attacks, you need to use Disable External Entities in your XML parser library (libxml2). Simply changing from one library or parser to another won’t protect you against XXE; you also need to upgrade libxml2 and libexpat itself if any patches were released.

This can be done by updating your application with npm update or yarn update on each platform you support.

Other security vulnerabilities to overlook when developing React Based Application

In addition to the React vulnerabilities we’ve covered here, there are also several other security vulnerabilities that you need to be aware of when building React applications:

Server-side rendering

Because server-side rendering does not require you to load the entire React app into a browser, it’s more secure than client-side rendering.

However, you will have to keep in mind that your React code is still vulnerable on servers, so make sure you follow best practices for security.

For example, avoid using dynamically generated data on a server (such as a user profile) because it cannot be validated by a browser. Instead, save all dynamic data in a database.

Also, make sure users are logged in before running any sensitive operations like creating accounts or updating profile data — if your server allows for anonymous requests, somebody could perform these operations without having any proper permission granted to their account.

Dangerous URI schemes

The default behavior for navigating with links is based on a URI scheme, which is how your browser knows how to go from one page to another.

You can use javascript: in place of a normal URL, but that opens up your app to XSS (cross-site scripting) attacks since that allows users to execute scripts and code in your browser using their own data.

For example, if you have an email input, they could run javascript:alert (‘XSS attack!’); in it, which would pop up an alert box with a message saying XSS attack.

Obviously, you don’t want that happening, so always prevent dangerous schemes like javascript:, VBScript:, etc., when allowing users to navigate via links.


Because of one little mistake, an attacker could change a perfectly harmless title tag into a block of malicious code. This example is just one of many flaws that have been found in React’s DOM. (And since React is so popular, more will probably be discovered.)

Fortunately, it’s not hard to avoid security vulnerabilities like these; ReactJS developers can take simple steps to protect the apps from attacks before they happen.

For example, you should always sanitize input data before sending it to JavaScript functions or binding it with HTML elements. And if you need access to content as plain text rather than HTML tags, you should use third-party utilities that explicitly handle escaping for you.

It’s important to note that these are only general tips; there are other potential problems depending on how your application uses React components, so don’t make assumptions!


As we have seen, React has become one of the most popular front-end frameworks and libraries. Due to its rising popularity, it is also becoming a target for malicious actors.

You need to be aware of some of the common vulnerabilities in React applications and take suggested steps to mitigate these risks.

In addition, you should also be aware of other security vulnerabilities that may not be specific to React but could still impact their applications. So, you can follow the best practices and secure your app but for this, hire dedicated development team working in the best ReactJS development company.



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Emma Jhonson

I am a technical expert, a passionate writer, and a seasoned IT professional for the last 5 years at