10 Ways to Improve Front-End Security and Not Get Hacked

At Foreworth, we take security and software performance seriously. That's why we are happy to share this guest-post from Pentest-Tools on how to secure your front-end against cyber-attacks.

Today's consumers handle banking, healthcare, shopping, and communications through digital gadgets. Customers expect to conduct business online safely and securely without having their money or personally identifiable information (PII) stolen. But the increased prevalence of digital devices has created opportunities for malicious entities to exploit web application vulnerabilities. 

Effective cybersecurity requires safeguarding every aspect of your network, as hackers will attack the weakest link they can find. It's critical to secure both the front and back end of the applications. 

The front end is the main entrance to the online business software application. It’s accessible to users or clients. Think of it as the front door of your home. Nearly everyone who visits will enter here. The back end is like a back door to a home. Only people with special access will be able to use it. 

Logically, the main door should be secured first. Since it’s visible to anyone on the street, you need to be extra careful that it’s locked to protect yourself. 

The front end of an application is what visitors see and engage with, whereas the back end of a website is the behind-the-scenes technology and operations that keep your website secure and operating. 

If hackers are able to find vulnerabilities in the front end of applications, they can intrude and cause great damage. 

Here are some security tips that can help improve the front-end security of web applications.

1. Sanitize input and output

You can sanitize the inputs to secure your web application from attacks like cross-site scripting (XSS), SQL injection, and XXE injection. Your website’s front end and back end should first validate the input before processing it. XSS happens when an attacker maliciously embeds JavaScript code into a legitimate website. 

Afterward, the attacker sends you more malicious code that seems to be the side script of your browser. 

Your browser executes the script as a result of an established trust for the website from which the scripts were supplied, which compromises your system. 

These malicious scripts can access your browser history, session tokens, personal information, cookies, and more. 

As far as output sanitization is concerned, you should encode the output when user-controllable data is sent in HTTP responses to stop the HTML parser from executing it. Depending on the output context, this may require combining HTML, URL, JavaScript, and CSS encoding. A library of output sanitization routines called secure-filters can be used to clean up HTML, JavaScript literal/strings, CSS, and a variety of other output types.

2. Ensure proper configuration of firewalls and routers

Distributed denial of service (DDoS) attacks can be effectively avoided by configuring routers and firewalls to refuse abnormally large and suspicious traffic. Make sure your routers and firewalls are updated frequently to have the most recent security measures. 

In a DDoS attack, your website would be subjected to an excessive amount of traffic that causes it to crash. The attacker would manipulate hundreds or thousands of systems to produce a lot of traffic directed at your web application in order to wear it out.

3. Implement CSRF tokens

Introducing random tokens in HTTP requests can assist you in thwarting cross-site request forgery (CSRF) attacks. Every time a form is submitted, your system produces the token value on each page of your web application and sends it to the form using a hypertext transfer protocol (HTTP) header. 

This is so the download action won't be carried out, and the attacker's intent won't be successful if the token is absent or doesn't match the one generated by your web application. 

Token value is important because it helps prevent CSRF attacks. These are where an attacker will trick you into visiting a site with malicious code while you’re logged into your website. There may be a download link, often to download a form. If you download the file, the hacker can exploit your site’s trust of your browser and gain access. 

Constantly entering your login information into websites that you visit frequently can also become tiresome. However, while keeping your login information on the website might make things simpler, it can make you vulnerable to CSRF attacks.

3. Self-host CSS servers

You can avoid falling prey to Cascading Style Sheets (CSS) injection-related attacks by self-hosting your CSS files on your own servers. To accomplish this effectively, you should also use a vulnerability management program to help you find potential flaws. 

A CSS injection attack becomes successful when an arbitrary CSS code is introduced to a reliable website and your browser displays the compromised file. 

Using CSS selectors, the attacker acquires unauthorized access to your sensitive information after injecting the code in the CSS environment.

5. Inhibit the use of vulnerable third-party libraries

A website’s information will be exposed and data can be stolen if the third party library is not adequately secured and experiences a security breach. 

For organizations globally, the average cost of a data breach is $4.35 million, and in the U.S. it’s $9.44 million. 

It’s necessary to implement third party libraries to improve the performance of the system. Using more of them allows you to do more functions on the web applications. However, occasionally these libraries can include security flaws that leave the systems vulnerable to online attacks. 

Regularly scanning your website for all the third party libraries will help you thwart attacks. Manually performing this can be difficult and time-consuming, especially when working with a sizable web application. However, the process can be automated by utilizing vulnerability scanners to find emerging risks and threats.

6. Implement a Content Security Policy

You’ve likely installed a web application that asked to access features of your device. This helps improve the user experience, especially in the development stage. 

However, if this feature is discovered by hackers, they use it to ask end user devices to grant malicious requests. It can be particularly difficult for your system to identify these as illegitimate because the requests are from your end. 

Configuring a Content Security Policy (CSP) can help end user devices not respond to requests from attackers if they get access to your system, even if they send them through your web application.

7. Use the appropriate response header

We can utilize Content-Type and X-Content-Type-Options headers to ensure browsers read responses how you intend. This prevents XSS in HTTP answers that aren't meant to contain any HTML or JavaScript. 

To avoid unintended execution, JavaScript Option Notation (JSON) data should never be encoded as text/HTML. According to the Secure Header Project of the Open Web Application Security Project (OWASP), response headers are used to strengthen application security by preventing browsers from exploiting vulnerabilities.

8. Utilize libraries with XSS protection mechanisms

Although HTML entity encoding is allowed when untrusted data is contained within a <div> tag, it’s ineffective when contained within a <script> tag. This is because HTML entities make it extremely simple to escape harmful characters. 

Thus, in some circumstances, HTML encoding is insufficient to prevent XSS attacks. Data context is also crucial. 

XML data, JavaScript code, and CSS must all be escaped in order to ensure web application security. So using libraries with XSS protection is necessary. 

The most well-known open-source library is provided by OWASP, called OWASP Enterprise Security API (ESAPI). 

You can make use of extra libraries for languages like Haskell, .NET, Java, and Python as well as other platforms. 

This aids programmers in creating lower-risk applications or implementing security upgrades.

9. Rely on specialized frameworks

Trusted sources offer specialized frameworks with embedded security that provide protection from serious design faults that affect security. 

They include the components that are required to secure web applications from vulnerabilities. Modern JavaScript framework has emerged as a crucial component of web development since it greatly lowers risk. 

Open source frameworks such as React, Vue, or Angular are used to build the majority of these web applications, and these are preferred over closed source frameworks. 

For instance, when utilizing innerHTML, Angular automatically sanitizes output and defends against different XSS attack vectors.

10. Use CAPTCHA for DDoS prevention

A CAPTCHA is a system or computer software designed to differentiate human users from robots. Bots are used in the majority of DOS attacks, so recognizing them before they can gain access stops them from submitting requests. 

Use CAPTCHAs on endpoints that are visible to the public, such as login, registration, and contact. A good solution for this is Google’s cutting-edge reCAPTCHA. This prevents bots from misusing your applications. 

Conclusion 

Cybercriminals attack at the first available chance. Your online application can be compromised in an instant if your front-end security is lacking or negligible. 

By sanitizing your input and output, ensuring your firewalls and routers are properly configured, introducing CSRF tokens, self-hosting your CSS servers, and following these other steps, you can help prevent malicious actors from accessing your system and causing damage.