Cybersecurity is intangible at first glance. However, all the unique features, attractive UIs, and seamless performance won’t matter unless your app is secure. These saddening statistics prove the previous statement:
As you can see, without a proper security layer in place, your application will often fall victim to hacks and attacks, leading to numerous re-testing and re-development rounds. This also applies to applications based on React.js, the first-most in-demand web framework in 2021.
Given that, if React.js is a prominent part of your app’s tech stack, you’re in the right place.
Table of Contents
According to Snyk, every time React.js makes an update, new security vulnerabilities that go unnoticed crop up. To this end, it’s impossible to encompass all possible cyberattacks that React.js (as well as any framework) might be vulnerable to. However, these four are the most common ones. Let’s explore them in more detail.
XSS is an injection of a malicious script into the code of a web application. The browser picks up this script and interprets it as legitimate. After that, the malicious code is executed as a part of an app. Here’s what the process looks like when the attacker injects an XSS code to steal users’ and visitors’ session cookies:
A successful XSS attack might enable the perpetrator to capture user input to steal their credentials, steal sensitive data from the app’s pages, send requests to servers, and beyond. More often than not, an XSS that goes unnoticed can lead to the full compromise of an app.
XSS is often confused with SQL injection (SQLi). However, the two are not the same thing. Though both imply malicious code injections, XSS makes users vulnerable while SQLi targets the application itself.
DDoS attacks overwhelm a web app infrastructure with more traffic than it is able to handle. Their purpose is to make an application inaccessible and unavailable to its users. Some of the most common ways to conduct DDoS attacks are UDP, ICMP, SYN and HTTP request flooding. Because a server and a firewall must process each request and respond to it, an attacker tries to exhaust resources, such as memory and CPU processing time.
XXE attacks occur in web applications that use XML (Extensible Markup Language), the text-based language utilized for storing and organizing data in a web app. For transforming XML into readable code, an app needs an XML parser. Such parsers often fall victim to XXE injections. Using XXE, a perpetrator can perform a CSRF or DDoS attack.
The problem is that XML parsers are vulnerable to XXE by default, so it’s up to your development team to make sure that the code is free from such vulnerabilities.
As described above, XSS, DDoS, CSRF, and XXE are the most common cyberattacks when it comes to web applications. But what exactly allows malicious code to slip into such apps? Below, we will explore security flaws specific to React.js, those common for all frameworks, and ways to fix them both.
When building a React-based application, you should watch out for the following vulnerabilities:
Let’s discuss each one in more detail.
One of the most prominent advantages of React is SSR (server-side rendering). This feature ensures a faster page load, better performance, and ease of incorporating SEO. Unfortunately, it makes React apps prone to attacks. Here’s why.
Most React apps use Redux for app state management, which uses JSON, a lightweight data-interchange format, to set an initial app state:
This is dangerous because “JSON.stringify” will not recognize sensitive data or XSS code. Although the example above also has code to mitigate simple XSS attacks, it’s not a silver bullet by any means.
It’s also worth mentioning that SSR opens a way for attackers to exploit vulnerabilities in third-party NPM packages.
URLs without a “http:” or “https:” protocol can allow malicious code to sneak into your React application. If such a URL is hardcoded, it’s harmless. But if it’s provided by a user, it poses a potential React XSS threat.
Unfortunately, React.js security features neither prevent the use of such links during development nor provide built-in defenses against their potential threats. This means that it’s up to your development team to ensure that they are safe.
Sometimes developers have to render HTML code coming from untrusted sources (user input, for example). The easiest way to render it in a browser is to assign it to the inner HTML attribute directly. Since it may cause XSS vulnerabilities, React.js limits its use by engaging the “dangerouslySetInnerHTML” property.
Unfortunately, this property doesn’t guarantee the code’s security and renders all the data whether its benign or dangerous. In fact, the role of “dangerouslySetInnerHTML” is to inform a developer that the code assigned to it might be insecure. Besides, it’s assumed that developers won’t use this feature without reading the documentation.
One of the key advantages of React is that it saves developers from manually putting data into the browser DOM to render components. However, there are cases when developers need direct access to the DOM elements.
For such scenarios, React offers escape hatches, such as “findDOMNode” and “createRef.”
Since an escape hatch returns the native DOM elements with their full API, the application can manipulate the element directly without going through React. This can lead to an XSS vulnerability.
The React.js security fundamentals listed above are effective. But when it comes to preventing some of the most common cyberattacks, they are no panacea. Though React.js stands out from the other libraries and frameworks, it isn’t immune to security concerns common for all frameworks, such as:
Compared to the server-side, the client-side is exposed to multiple actions performed by users. That’s why the client-side authentication and authorization often fall victim to security flaws. So, how can you prevent these flaws? Follow the checklist below:
To further secure your React authentication, consider the following:
Make sure that all the limitations and restrictions on authorized users are sufficient. Ignoring this rule can lead to any user being able to access unauthorized control features. Given that, consider the following:
Unfortunately, no framework follows all security measures by default. React is no exception. Vulnerabilities often occur as a result of incomplete security configurations or improperly built HTTP headers. Given that, it’s critical to incorporate security testing into the development process and conduct regular monitoring for security flaws during the entire lifecycle of your app.
So, how can you stay vigilant to your React app’s security configurations? Below are some tips:
Even a mismatch in APIs may lead to sensitive data exposure. To prevent this, follow our tips:
Providing end-to-end encryption is critical. This type of encryption secures the data exchange between end users, being a user’s browser and your servers or between your distributed services. The lack of the end-to-end encryption accounted for the majority of data breaches in 2019.
In many cases, React alone has nothing to do with your app’s vulnerabilities. The use of third-party libraries, modules, APIs, and frameworks might allow security flaws to sneak into your application. Luckily, implementing the React web app security solutions listed below will protect your app against these “externally originated” vulnerabilities:
|DoS and DDoS||During and after the development stage, scan the entire React app for known DDoS vulnerabilities. Install visitor identification. Use CAPTCHA or JS tests against DoS.Consider tools like Cloudflare to mitigate possible and ongoing DDoS attacks.|
|CSRF and arbitrary code execution||Use JWT tokens for session management.Make sure that your application reads only the stored CSRF tokens.Ensure it generates only relevant headers upon authentication.|
|XXE||Avoid serialization of confidential data.Make sure that the XML parsers are updated.Use SAST tools to scan your code for XXE.|
|SQLi||Validate API call functions against respective API schemas.Escape all incoming data or use proven ORMs.|
As you can see, securing a React web application is a complex process, which requires several (it depends) cybersecurity experts specializing in React.js. Still, if you don’t have these in your in-house team, you have at least two options to choose from. You can hire cybersecurity developers them from scratch or outsource the task to a software development vendor, such as Relevant Software.
Due to our security-first thinking, we have helped multiple companies comply with the OWASP’s Top 10, GDPR, and ISO 270001. With React.js and Node.js being our main tech stack, we’ve built more than 100 secure web applications, which you can find in our case studies.
With that being said, whether you are looking for QA engineers to test your existing React.js solution or need experts to build one from scratch with all security measures in mind, don’t hesitate to drop us a line.