What is a Web Application Firewall (WAF)?

A Web Application Firewall or WAF helps protect web applications by filtering, monitoring, and blocking malicious cyber attacks and also prevents sensitive data from being breached or leaked. Every WAF adheres to a set of rules or policies to prevent cyber threats from compromising the organization’s data and reputation. It also helps keep an eye on the web application traffic to keep it at bay and ensure that malicious websites do not harm the organization’s information. 

A proxy server is used to protect one’s identity from being exposed and misused; in the same way, a WAF does the exact opposite and enables the safeguard of an application’s server from malicious attack actors, hence known as the reverse proxy. 

What is the importance of a WAF?

WAF plays an important role for organizations and businesses that offer products and online services. Most companies usually store sensitive data in backend web applications. Web Application Firewall (WAF) provides security to these applications to secure sensitive data from leaking, being stolen, and misused. Information such as customer records, payment card details, and so on are the kinds of sensitive data that these web applications carry. 

To facilitate business interaction, companies are increasingly employing applications and IoT devices. This shows that many online transactions occur in the application, making it an easy target for attacks to reach for data. Using a Web Application Firewall (WAF) helps meet compliance standards such as PCI DSS (Payment Card Industry Data Security Standards). Thus, a WAF is more than essential to an organization’s security model.

As important as WAF is in securing data, it is recommended to implement other security measures, such as an Intrusion Detection System (IDS) and Intrusion Prevention System (IPS), to achieve an impenetrable defense security system. 

How does a WAF function?

Web application firewalls monitor and filter network traffic that uses web protocols, particularly HTTP and HTTPS so that vulnerabilities in web applications can be protected.WAF functions in two distinct ways: protecting inbound and outbound traffic.WAF inbound protection functionality inspects application traffic from the outside world. The WAF must identify dangerous activity patterns, suspicious payloads, and vulnerabilities to protect the web application from inbound traffic.

For a WAF to function, proactive security policies need to be set up to protect against known vulnerabilities in a web application. As attack vectors evolve, each security policy must be updated to filter out different types of malicious traffic. Web application firewalls are effective when designed for security policy modifications.

The purpose of outbound protection is to prevent leaks of enterprise data and customer data. It is extremely challenging in the real world to determine outbound data accurately. However, proxy-based, inline WAFs can intercept outbound traffic and mask or block sensitive information from leaking.

Benefits of a WAF

A Web Application Firewall (WAF) offers several key benefits for organizations. Here are some of the main advantages:

1. Enhanced Security:

   A WAF inspects and filters incoming traffic to enhance web application security. This prevents attacks like SQL injection, cross-site scripting, and cross-site request forgery (CSRF). By blocking malicious traffic, a WAF prevents unauthorized access and data breaches.

2. Vulnerability Mitigation:

   WAFs can detect and mitigate known vulnerabilities in web applications. They often come with predefined security rules that can be customized to match specific application needs. This helps address security weaknesses and reduces exploitation risk.

3. Real-time Threat Monitoring:

   WAFs continuously monitor and analyze web traffic for potential threats. They can detect suspicious patterns, abnormal behavior, and known attack signatures. With a WAF, organizations can respond to potential security incidents in real time.

4. Regulations and compliance requirements:

   Many industries have specific requirements for securing web applications. A WAF can help organizations meet these requirements by providing a robust security solution. An audit of this demonstrates a commitment to data security.

5. Performance Optimization:

   WAFs also enable web applications to perform better while protecting them. Their functions include caching static content, compressing data, and optimizing network traffic. The WAF can improve response times and reduce server load by offloading some processing tasks.

6. Flexibility and Customizability:

   WAFs offer flexibility in configuration and customization. Security policies and rules can be customized to meet specific application requirements. By adapting to the organization’s unique needs, the WAF is designed to meet its needs.

Three ways of implementing a WAF

1. Network-based WAF – Network-based WAF is usually hardware-based and installed locally to minimize latency. This type of WAF is expensive and requires maintenance of physical equipment.

2. Host-based WAF – A host-based WAF can be fully integrated with an application’s software. However, it requires extensive local server resources, is complex to implement, and can be expensive to maintain compared to network-connected WAFs. Hardening and customizing a machine for a host-based WAF can take time and money.

3. Cloud-based WAF – A cloud-based WAF is an affordable, easy-to-implement security solution that does not require an upfront investment, and users pay a monthly or annual subscription fee. Users can update their cloud-based WAF at no extra cost and without much effort. Since you rely on a third party to manage your WAF, it is important to make sure cloud-based WAFs have enough customization options.

What is the future of WAF?

According to many experts, the future of firewalls lies in something other than adding more sophisticated traffic filters. In the future, firewalls will have an innovative delivery model that makes them easier to deploy and more appropriate for modern IT environments. Here are a few advanced firewall solutions that use innovative delivery methods, making them essential components of the new cloud-native environment.

Firewall as a Service (FWaaS)

Firewall as a Service (FWaaS) offers cloud-based network traffic inspection capabilities to customers who want to replace traditional firewall appliances. Using this approach, the firewall infrastructure is managed by a cloud vendor instead of on-premises. As a differentiation strategy, FWaaS providers typically provide advanced cybersecurity capabilities within the NGFW feature set. Security as a service solutions provide intrusion detection, application-aware security policy enforcement, URL filtering, threat intelligence, and advanced malware protection.

Secure Access Service Edge (SASE)

SASE open-source networking framework solves the problem of remote access; data center is not required to handle external traffic networking and security. The situation is critical for organizations with cloud workloads whose security and networking infrastructure remain on-premises.

The SASE framework includes next-generation firewall capabilities. The firewall is not just delivered as a service but is integrated with the entire network stack, so it goes beyond FWaaS. As a result, it provides even better security due to a reduced chance of misconfigurations.

Conclusion

Web Application Firewall (WAF) is a security measure for web application companies. Cyber attacks are prevented, data breaches are prevented, and compliance with industry standards is ensured. The WAF role is to provides enhanced security, real-time threat monitoring, and performance optimization by monitoring and filtering web traffic, identifying malicious patterns, and addressing vulnerabilities.