Best Practices For Securing A ReactJS Application

best practices to secure reactjs app

According to the most recent StackOverflow developer survey, React.js is the second most popular JavaScript framework for web development. It’s a powerful tool for designing interactive and dynamic user interfaces. A Reactjs development company uses React.js to construct massive web applications with quick performance and simple scalability.

The following are the primary characteristics that make React.js a popular web development technology:

Reusable components for a consistent app appearance and easier app development;

  • The use of a virtual DOM provides for faster web page rendering and enhances app performance;
  • A high abstraction layer that simplifies app development even for React.js newcomers;
  • Flux is a Facebook architecture for managing simple data flows in React.js apps;
  • Redux is a state container that organises React.js apps, making them consistent and easy to test;
  • A variety of development tools and extensions.

Most Common React Application Security Threats

  • Cross-Site Scripting (XSS): Cross-site scripting (XSS) is a significant vulnerability that occurs when an attacker successfully tricks a web app into executing JavaScript code. Cross-site scripting can be further divided into two types:
  • Cross-Site Scripting was Reflected: It occurs when a web app receives malicious JavaScript code in the shape of an HTTP request from a trusted source. This code is then parsed by the app’s browser. As a result, the malicious script has access to the browser’s cookies, session tokens and other sensitive data. These scripts can also modify the HTML page content or carry out undesired actions that a user could carry out.
  • Cross-site scripting that is saved: The stored XSS was obtained from an untrustworthy source. A web app keeps harmful stuff on a server or in a database for later use. When a user requests the stored data, the script begins working on the server-side, creating data and sending it to the user.
  • Authentication Error: The unsecured connection between the web client and the server-side causes authentication and user authorisation concerns. Hackers can disrupt authentication and authorisation processes, compromising user account data, passwords, session tokens and other things.

The following are the most common React.js security risk factors associated with failed authentication:

  • exposing session IDs in URLs; 
  • basic or easy-to-predict login credentials; 
  • session IDs and passwords sent across unencrypted connections
  • session fixation attacks, in which sessions are not invalidated when a user logs out. 

But by availing of reactjs development services, companies will be able to reduce the risks of such errors.

  • Injection of SQL Data: This kind of attack targets the app’s databases. Attackers can gain access to data by injecting malicious SQL code into a database. They can update, delete or create new records if they have admin privileges. SQL injections come in a variety of flavours, including error-based, time-based and logical-error-based attacks and React apps are vulnerable to all of them.
  • XML External Entity Attack (XXE): XXE attacks occur in web applications that employ XML (Extensible Markup Language), the text-based language used in web apps to store and organise data. An XML parser is required for an app to convert XML into understandable code. Such parsers are frequently targeted by XXE injections. A CSRF or DDoS attack can be launched with the help of XXE. The issue is that XML parsers are by default vulnerable to XXE, so it is up to your reactjs development company to ensure that the code is clear of such flaws.
  • Zip Slip: Zip Slip vulnerability occurs when app users submit small zip files in React.js apps. When such files are decompressed by a web program, they are returned to their original size. Some of these files may include hacker codes that allow attackers to get access to the system. Attackers can use this React.js flaw to replace the files responsible for app settings and data storage. They can use Zip Slip to break into the app’s system on the client or server-side.

Arbitrary Code Execution: An attacker’s ability to execute arbitrary commands or code on a target process is sometimes referred to as arbitrary code execution (ACE). An arbitrary code execution vulnerability is a software or hardware security defect that allows arbitrary code execution. An arbitrary code execution exploit is a program that is designed to exploit such a vulnerability. This vulnerability is dangerous because if it arises in a public product, it will expose all users to it.

React.js Security Best Practices

Knowing the most prevalent React vulnerabilities makes it easy to come up with a solution and defend against the recognised attacker. For good application security, you must pay close attention to the complete website’s development, including your web application, web server configuration, password creation and client-side code.

Taking into consideration the React risks stated above as well as the React security resources, we’ll go through some of the most common and basic methods you may take to defend your React.js application.

Basic Authentication is Secure: Making sure the connection between the server and the client is safe is a fundamental yet important principle for the security of your application. When developing your application, an easy approach to accomplish this is to verify that the domain header contains a realm property. A realm stores a list of valid users and requires a username and password to access any restricted material.

Make sure that the HTML code is resilient: Because any React application will require HTML to render it, it is critical to ensure that your HTML code is secure. There are three positive approaches to accomplish this:

  • HTML markups should be disabled 
  • Make use of Escape Characters
  • Use with caution SetInnerHTML and HTML sanitization

When Parsing URLs, Use allows/block Lists and Validation: When utilising the anchor tag a URL to link content, be wary of attackers including payloads prefixed with JavaScript. Always validate the URL using the HTTP or HTTPS protocols to avoid URL-based malicious script injection.

The allowlist/blocklist method is another method for securing your React application. Allow listing refers to having a list of all the links that are safe and allowable to be visited, whereas blocklisting refers to having a list of all potential risks that will be prohibited if access is sought.

Protect your React APIs: The good and bad thing about React APIs is that they allow you to link your project to other services. These are capable of storing data and even executing commands. This makes your app vulnerable to XSS and SQL injection. Validating all API functions against their API schemas is a powerful mitigating technique against this problem. Also, schedule schema validations on a regular basis and employ SSL/TLS encryption for all transactions.

HTTP Authentication: There are many apps that require authentication when a user logs in or creates an account and this process should be safe because client-side authentication and authorisation are vulnerable to several security flaws that can damage these protocols in the application.

  • Install a Web Application Firewall: A WAF is an application filter that monitors, analyses and filters bidirectional traffic to detect and block harmful information.

There are three approaches to set up a web application firewall:

  • A network-based firewall that is hardware-based
  • A host-based firewall is included in the software
  • WAF in the cloud

Include End-to-End Encryption: End-to-end encryption ensures that only the parties involved can read the messages. It is enabled by encryption technology, which ensures that the communication is encrypted as soon as it leaves the sender and can only be read once it reaches the intended recipient.


Making your React app secure can be quite complex and tough, with new risks emerging every day and attackers abusing more and more weaknesses.

You can either engage React developers who specialise in security or outsource the development to a firm providing reactjs development services. Make sure you have an expert on your side when it comes to security.