How the Web Application Firewall Protects Your Data and Website

Just like everything else on the Internet, web applications are constantly under attack from hackers. In fact, web applications are involved in 26% of data breaches. 

The Web Application Firewall or WAF is a security solution that is designed to  protect web apps and their data from malicious attacks. In this blog we're talking about how the WAF protects your web application and how it works.

What is a Web Application Firewall?

A web application firewall (WAF) is a firewall that is designed to protect web applications from attacks such as cross-site scripting (XSS), cross-site forgery, file inclusion, malicious SQL injection, and other attacks. It also protects your data from being stolen or compromised. While a network firewall (firewall) is designed to protect the network and defend against a broader range of attacks, the WAF is focused on the web application only. The main objective of a WAF is to detect and block malicious traffic and prevent the exploitation of web applications. Essentially, the WAF is a security layer that is placed between the web application and the internet. 

How Does a WAF Protect You?

When a WAF is deployed in front of the web application, it creates a barrier between the web application and the internet. Its main function is to filter and monitor the HTTPS traffic that comes in from the internet. 

The WAF runs on a set of rules that determine which traffic should be allowed to pass through and which traffic should be blocked. These rules are known as policies. The WAF will be configured to match the security requirements of the organization and its web applications. The policies of a WAF can be based on different criteria, and can be modified at any time.

WAFs are deployed at the  application layer or Layer 7 of the OSI model of the internet. No other type of firewall can be deployed at the application layer. Because of this, it provides greater visibility into sensitive data that flows through the web application. 

There are primarily two approaches a WAF can take to filter traffic: whitelisting and blacklisting. Whitelisting is to block traffic by default and only allow traffic from certain IP addresses or domains that are known to be safe. Whereas, blacklisting is to allow traffic by default and block traffic from certain IP addresses or domains that are known to be malicious. Sometimes, a hybrid approach is used where the WAF will use a mix of both whitelisting and blacklisting to filter traffic.

WAF Deployment Options

• Network-based WAF - Network-based WAFS are usually hardware-based devices that sit at the network layer of the OSI model.  They are placed locally and on-premises, as close to the application as possible, using dedicated and specialized equipment. 
• Host-based WAF - A host-based WAF is installed into the application's software. 
• Cloud-based WAF - Cloud WAFs are straightforward to deploy, offered on a subscription basis, and frequently require only a simple DNS or proxy update to divert application traffic.

Each of these options has advantages and disadvantages. For example, network-based WAFs have high performance and scalability, but are expensive to maintain and are usually difficult to integrate with other security solutions. Host-based WAFs are inexpensive to deploy, but require specialized expertise to manage, are vulnerable to exploitation, and have limited scalability. Cloud-based WAFs have low deployment and management costs, but require updates and patches to ensure they are working correctly. 

Choose a deployment strategy that matches your business requirements and your level of technical expertise. Remember that with a WAF, you have to keep it up to date to maintain its effectiveness,  so keep this in mind when considering any given deployment strategy.

Benefits and Drawbacks of Using a WAF

There are many benefits to implementing a WAF, such as: 

• It protects web applications and APIs against different types of external attacks such as SQL injection, cross-site scripting (XSS), DDoS, and many more. 
• WAFs use signature-based detection technology to identify threats - meaning that they have a database of unique identifiers for threats that they use to detect attacks. 
• They are known for their ease of deployment and can be integrated into cloud-based and on-premise environments. 
• Policies for blocking and allowing traffic can be modified easily and implemented quickly, allowing for faster threat detection and response times.

While a WAF can be a powerful tool in your security arsenal, there are also some potential drawbacks to using one. 

For starters, a WAF can add latency to your website. This is because it takes time to inspect each web request and response to make sure there's no malicious activity happening. Another potential drawback is that it can be difficult to properly configure a WAF. If it's not configured correctly, it can end up blocking legitimate traffic or failing to block malicious traffic. And finally, a WAF can be bypassed. So while it's a good security measure, it's not foolproof. But when used in conjunction with other security measures (like SSL/TLS), it can be an effective way to protect your data and website.

How to Choose the Right Web Application Firewall

With so many web application firewalls to choose from, it can be difficult to determine which one is the best for you. Here are some things to consider while making your decision: 

• Is the WAF capable of defending against a broad range of attacks including the most common types of threats and can it quickly identify and block new attacks? 
• Do you have adequate options to tailor the protection to match your specific needs?
• Can the WAF protect itself from targeted attack attempts? 
• Does the WAF meet essential compliance requirements? 

We hope that  these suggestions will help you in choosing the right web application firewall for your needs. 

Conclusion

Web application firewalls provide a robust layer of protection against a wide range of malicious threats. However, just a WAF alone cannot protect your applications from all threats. When used in conjunction with other security measures, it can prove to be a valuable tool that can help protect your web applications. It is important to choose one that is tailored to your specific needs, and remember to keep it up to date in order to maintain its effectiveness. By doing so, you can ensure that your data and web apps are safe from any potential attacks.