Top React Security Vulnerabilities & Best Practices to Avoid Them

Skein Technologies
7 min readDec 23, 2020

React also known as React.js or React JS is a framework that is maintained by Facebook for building user interface or UI components. It was initially released as a prototype by Facebook and was called ‘FaxJS’. In 2011, it was deployed as an integral part of Facebook’s news feed.

Since its initial release in 2013, React has grown to become one of the most widely used JavaScript libraries for the development of mobile applications.

Some leading companies like WhatsApp, Facebook, Instagram, and Netflix use React as a core part of their technology stack. This is a testament to React’s reliability and success. It is one of the most loved platforms amongst the development community across the globe.

There are some clear advantages that React offers, which makes it so successful. Let us first briefly understand why React is favored over many other alternatives.

Advantages of React

Here are some advantages that make React a preferred alternative:

a) Faster Rendering

React has heavily worked upon rendering, which is one of the most time-consuming problems in mobile development. React offers quick rendering, which enables developers to make quick changes throughout the development cycle

b) Reuse of components

It is extremely easy for developers to learn about React components even if they have a basic understanding of JavaScript. Developers can reuse these components throughout their development.

c) Flexibility

ReactJS offers developers more flexibility than any other alternatives. This helps in efficient development that saves development costs and time.

d) SEO-friendliness

Search engine optimization is extremely important in today’s competitive market. ReactJS offers SEO-friendly code development that significantly improves the visibility of your mobile application.

Advantages like these have made ReactJS extremely popular amongst the developer community. However, like every framework, React does have certain security vulnerabilities.

If you are planning to develop a mobile application using ReactJS, it would be a good idea to go through this list of React security vulnerabilities and React security issues so that you can avoid problems. You will also have a good understanding of React security best practices so you can be better prepared before starting your development.

Security Vulnerabilities in ReactJS

The following can be regarded as a React Security Checklist. It mentions the most common vulnerabilities in ReactJS and how these issues can be avoided or fixed.

a) Cross-site Scripting

Cross-site scripting also called XSS is one of the most common vulnerabilities with ReactJS. This is a client-side vulnerability. In cross site scripting, an attacker manages to trick a website. This is done by running an arbitrary JavaScript code over the client’s browser. An attacker thus gains control over the client’s data and can disrupt the entire structure.

Cross-site scripting is generally categorized into two broad types:

  • Reflected cross-site attack
  • Stored cross-site attack

In reflected cross-site scripting, a link containing sensitive information is filled into a page and read as code in the browser.

In stored cross-site scripting, something uploaded on the server by an attacker gets rendered on a page. Comments or image uploads are a common way to achieve stored cross-site scripting.

Cross-site scripting can lead to a data breach, data theft, or an attacker can force your application to go haywire.

A potential solution to avoid cross-site scripting:

The first step to avoiding this is to spot it in code. You can try looking for JSON.stringify() function being called, which might have suspicious data under its script tag.

Another measure you can take is to disable markup that might hold instructions to execute a suspicious code. This will help secure your React application and help you avoid a potential security breach.

It is important to be cautious with a cross-site scripting attack. Ignorance can lead to major problems that can cost a lot of time, money, and efforts to correct.

b) SQL Injection

SQL injections can be one of the most harmful threats while using ReactJS. SQL injections are security vulnerabilities that allow an attacker to get access to user credentials bypassing all permissions. Attackers can execute arbitrary SQL code snippets and gain access to user credentials. They can also modify data once they have gained access.

Through successful SQL injections, attackers can build fake credentials, gain admin privileges, and exploit user privacy on a big level.

SQL injections are of three main types:

  • Time-based SQL injection
  • Error-based SQL injection
  • Logic-based SQL injection

A potential solution to avoid SQL injection:

To avoid SQL injections, it is important for ReactJS developers to monitor and validate API call functions against their respective API schemas. The objective here is to ensure a match and check for any conflicts or suspicious activity.

Timely validations can go a long way in ensuring any suspicious activity does not go unchecked. If API schemas are not validated regularly, it can be very easy for attackers to inject malicious code snippets and activate an SQL injection.

Another simple way to discourage an SQL injection is to purchase an SSL certificate. An SSL certificate is not costly and is a yearly investment that can go a long way in securing your applications.

Connect with us today to find out more about SSL certificates!

c) Server-side Rendering

When a developer is rendering an application from the server-side, they are increasing their vulnerability. This is a type of XSS injection that is more commonly called a server-side rendering attack.

Developers usually create a document variable from a JSON string itself while building a page in ReactJS. Since the JSON string converts data into a string, it increases the chances of vulnerability. Such a string can then be rendered into a page causing a successful attack.

A potential solution to avoid server-side rendering vulnerabilities:

To avoid a potential server-side rendering vulnerability, it is important for developers to escape the rendered JSON. This can be done by using the serialize JavaScript with the NPM module.

Besides this, it is important to monitor and validate any failures on the server-side regularly and report on time.

d) Insecure Randomness

User-supplied data makes up most of the portion of an application. If an attacker inserts a link that starts with JavaScript, it can cause insecure randomness. If a user clicks this malicious link, attackers can easily get access to user credentials and take control. They can then proceed to modify sensitive information by overriding admin privileges.

A potential solution to avoid insecure randomness:

While building your applications make sure you use white-listed protocols and leverage HTML entities. You can also isolate the suspicious code from the rest of the code body for further inspection if the problem persists.

e) End-to-end encryption

In a world that faces increased threats from data breach and data theft, it is extremely important to consider end-to-end encryption while building a mobile application using ReactJS. Most of the vulnerabilities can be avoided if your data is encrypted.

While building an application in React, developers often integrate third party API’s to simplify development. This can also expose your application to vulnerabilities and attacks. Once a developer gains access to your data through a leak, it is pretty easy for them to manipulate sensitive information and override control over your product.

A potential solution to build end-to-end encryption:

End-to-end encryption can be best implemented with the use of a private and public key. This helps in securing your codebase as every possible entry point requires a key match. You can also implement some asymmetric algorithms like RSA to further bolster your encryption.

ReactJS also provides the cryptojs and encryptjs libraries that should be implemented while encrypting your application data.

f) Zip slip

When developers use a vulnerable library to unpack an archive, malicious code can be injected and attackers can exploit this opportunity. Once they gain access, they can easily modify credentials and gain complete control. This can happen with any type of configuration files or executable files. Attackers can remotely access arbitrary code and control your application data.

A solution to avoid zip slips:

Developers can start by using consistent versions of archive processing libraries. It is important to cross-check and verify code and inspect it regularly for any suspicious activity. Building test cases as part of a zip slip testing protocol is usually a good idea. Tools like Sync can be used to scan for vulnerabilities to avoid possible threats.

Find out more about Zip Slip — Contact us today!

Build ideas with React

We hope this article gave you the necessary insights in understanding some of the React security flaws. While it seems like React is vulnerable to many attacks and threats, it still continues to be one of the most successful platforms for building wonderful web applications.

Besides, xss vulnerabilities are a part of technology. It is simply important that you be aware of the threats while building react applications and know how to fix them.

Furthermore, React has successfully managed to bolster its security pitfalls and attacks over the years and has garnered a strong community that provides you with support and resources. It is definitely here to stay and improvise further in becoming a robust and reliable approach to build great ideas.

Originally published at https://www.skeintech.com.

--

--