Web Application Firewall (WAF)

What is a Web Application Firewall and how does it work?

A web application firewall (WAF) acts as a powerful filter to protect web applications from a variety of cyber attacks. Designed to monitor, assess, and, if necessary, block traffic, WAFs function a lot like fences: they are placed between the application and the main requests that arrive from the internet, thereby providing a significant layer of protection. This is made possible by the WAF's strict adherence to detailed policies that determine which types of traffic are safe and which could prove dangerous. These are sometimes referred to as reverse proxies, as WAFs protect servers from possibly malicious clients.

What attacks are blocked by this solution?

WAFs are designed to identify and block potential application-layer attacks. These often involve injection attacks such as cross-site scripting (XSS), in which seemingly safe websites are injected with malicious code. Similarly, WAFs prevent SQL injection, involving attacker interference into queries between applications and their databases. WAFs can also be a powerful deterrent against distributed denial of service (DDoS) attacks, as these solutions are specifically designed to block or limit traffic that appears malicious. Without WAFs, cookie or session hijacking can also be a huge source of risk.

What is the difference between WAFs and firewalls?

WAFs should not be confused with network firewalls. The former delivers a more targeted approach, rather than being used to provide broad protection for the network in general. Meanwhile, network firewalls provide comprehensive protection. The location of these firewalls determines their functionality, with network firewalls placed at the edge of the network — rather than in front of the application, as is typically the case for WAFs. The ideal security solution will incorporate both WAFs and general network firewalls.

Why should I use a WAF?

WAFs are a critical tool for shoring up security, especially when gaps threaten web applications. This proactive solution provides continuous filtering and protection to provide a targeted form of security that cannot be accomplished with HTTPS alone. Despite providing a high level of protection against today's most alarming cyber threats, WAFs are typically easy to implement and highly cost-effective. This makes them an all-around wise investment for a variety of businesses that rely on optimally-functioning web applications.

What are the three types of WAF?

Web application firewalls can be software, hardware, or cloud-based. Installed locally and deployed via hardware appliances, hardware-based WAFs are among the most expensive to implement but can also produce the best speeds and performance. Software-based WAFs deliver greater customization opportunities, as they are fully integrated within application software. Cloud-based solutions harness the power of cloud infrastructure to provide quick implementation and low prices. This is the most user-friendly solution.

What does SiteLock’s Web Application Firewall cover?

• Bot mitigation to block bad bots

• Includes real-time traffic statistics and reports

• Includes a premium content delivery network (CDN) to increase website speed

• Advanced static and dynamic content caching

• Sophisticated threat protection from the OWASP Top 10 cyberthreats

• Provides fully secure end-to-end encryption for SSL certificates

• Prevents search engine blacklisting

• Improves search engine optimization (SEO)

• Eliminates comment and form spam