Secure JavaScript Applications

The Only Way to Build Effective and Secure JavaScript Applications

Jul 20, 2016 By Paul Curran

JavaScript is everywhere. It runs on your smartphone, personal computer and even on your server. That much power comes with a lot of responsibility. Keeping JavaScript code clean and secure is the only responsible way to write JavaScript.

Given the vast proliferation of JavaScript, there is a myriad of ways to write poor code as everyday hackers target popular languages and come up with innovative exploits. This leaves an interpreted language such as JavaScript vulnerable unless you take the proper defensive measures.

Let’s examine the ways you can write clean and secure JavaScript.

Why JavaScript?


JavaScriptʼs popularity comes from the fact that it is the language of the browser, making it the only alternative to writing rich client applications on the web. With this much reach, developers have a duty to write effective and secure code. More and more business logic lies on the browser and relies on it to give the best experience to their users. There are many reasons for this, including a richer and more flexible interaction with the user and faster response times. Users expect solutions that are responsive and easy to use. When JavaScript is poorly written and not sufficiently protected, devastating consequences may occur for a business using potentially vulnerable JavaScript code.

javascript vulnerabilities

Popular JavaScript frameworks


Despite the risks, however, the natural choice is JavaScript for many businesses. It runs on the browser with no installs, and it is easy to deploy in an organization. This keeps maintenance costs low and customers get continuous updates with no hassle.


The story of JavaScript doesn’t end with the browser, however. JavaScript runs on the server as well as on the Node.js framework, making JavaScript a production-ready language meant for professionals. As with any other language, there are specific ways to write clean and secure JavaScript code.


The good news is there are tools that can help ensure the security of your JavaScript code.


SAST (Static Application Security Testing) and its Benefits


SAST helps you write clean and consistent code. There’s tremendous value in a product that can spot errors immediately, as many experienced developers will tell you. A strong SAST tool will make a developer more effective in finding bugs and producing high-quality code. With source code analysis SAST solutions, developers can quickly find problems at the root, which is the source code.


checkmarx secure software development lifecycle

Checkmarx integration with each of the development touch points in the SDLC [CLICK TO ENGLARGE]

Human beings are good at writing creative JavaScript that solves business problems, while computers are superior at spotting inconsistencies that lead to code flaws and bugs. Harnessing the power of a developer along with a strong source code analysis solution is one of the most powerful tools in your arsenal.


One example of such a solution is Checkmarx. Checkmarx is a static code analysis solution designed to scan and identify problems at the root, providing the best way, and place, to solve each vulnerability. Using Checkmarx will make you, the developer, more proficient at writing clean and sound code. Checkmarx tightens the feedback loop as it warns about problems before the code has been compiled, saving you from having to make last-minute code fixes. A tight feedback loop and secure software development lifecycle (sSDLC) will keep you effective while letting the tool handle all the minutiae.


Keep Code Secure and Make It Defend Itself


Jscrambler is a platform that delivers secure JavaScript capable of defending itself. It works by obfuscating code, adding code traps, and giving it self-defending capabilities to prevent tampering of your application. It can also notify you when an attack occurs so you’ll be always fully aware of what’s happening to your assets.


With an interpreted language like JavaScript, the risk of code tampering on the browser is real. One of the most common JavaScript security issues is Man-in-the-Browser attacks, a form of Man-in-the-Middle. These attacks have no fingerprint on the server and up until now there was no way to detect them. They allow the attacker to tamper with the application (including changing JavaScript on the client) as it is exposed, tricking the user to impersonate it and ultimately the backend. This means that protecting the server doesn’t prevent it from processing a fraudulent request from the client-side.


This results in users and customers that lose trust in your capability to deliver secure applications. With Jscrambler it is possible to detect these malicious requests and act upon them, thus preventing business losses and damages in reputation.

How Jscrambler protects JavaScript applications

How Jscrambler protects your application


Jscrambler applies the best of obfuscation and Client-side RASP (Runtime Application Security Protection) techniques to make JavaScript secure in runtime. This way you can be sure your application is safe and focus more on delivering real business value.


Delivering High-Quality Software That Doesn’t Put Your Business at Risk


Combining Checkmarx with Jscrambler will enable you to deliver high-quality and secure JavaScript applications. If you are a professional in charge of delivering value, this will help you achieve just that. Your customers demand sound and secure solutions, and stakeholders expect no less. The right set of tools can protect you from attackers and help you write secure JavaScript.


The result of having the best tools is your code quality increases. This puts you in a better position to add more value to your customers. Most importantly, it makes you happier at work. Code that is clean, secure and meets deliverables is great for all parties involved.


In your next coding adventure, we hope you’ve considered the many pros of having the right tools. From our experience, using the best tools only makes you more effective at building excellent solutions.

This post is a guest post from the team at Jscrambler, the leading JavaScript Security platform which is available as both a Web application and Web API, in the cloud or on-premises. To learn more about how you can use Jscrambler to protect your JavaScript, check out their website.

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If you’re passionate about secure JavaScript development, be sure to read The Top 3 JavaScript Frameworks for Web Applications and their Unique Vulnerabilities


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Paul Curran

Content Specialist at Checkmarx
With a background in mobile applications, Paul brings a passion for creativity reporting on application security trends, news and security issues facing developers, organizations and end users to Checkmarx's content.

Latest posts by Paul Curran (see all)

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