Web Application Firewalls: Everything You Need to Know (WAFs)

What exactly is a WAF?

A Web Application Firewall (WAF) is a form of firewall that guards against harmful application-based assaults.

In layman’s terms, a WAF serves as your WordPress site’s middleman or security guard.

It will assist defend online applications against cross-site scripting (XSS), cookie poisoning, SQL injection, cross-site forgery, and other types of threats.

WAFs will function as a barrier between the internet and your web applications, monitoring and filtering HTTP traffic destined for your server.

It does this by following rules that aid in distinguishing which traffic is malicious and which is not. WAF works in a similar fashion to how a proxy server protects a client’s identity by acting as a mediator — but in reverse.

It’s a reverse proxy that protects the web application server from a potentially harmful client by acting as a go-between.

WAFs are a collection of rules (or policies) that can help you figure out who’s on your guest list and who’s simply seeking for trouble.

Network Firewalls and WAFs

WAFs are not to be confused with traditional Network Firewalls (Packet Filtering), which evaluate incoming data based on a set of criteria such as IP addresses, packet types, port numbers, and more.

Firewalls on networks are fine and excellent at what they do. The main drawback is that they don’t comprehend HTTP, thus they can’t identify particular attacks that target web application security weaknesses.

That’s where WAFs come in, and they can help you secure your website in ways that a Network Firewall can’t. It has a lot of layers to it.

Using various security methods may also help you safeguard the individual levels even further.

The OSI Model (Open Systems Initiative)

To comprehend these levels, you must first comprehend the OSI Model (Open Systems Interconnection Model).

The OSI model is a framework for dividing a network’s overall architecture into seven sections.

Every layer has its own security postures and procedures, and anybody who is concerned about security should be able to identify and implement suitable security measures for each.

When looking at the layers above, a normal Network Firewall helps secure levels 3–4, whereas a WAF helps secure layer 7.

It’s also worth remembering that WAFs aren’t a one-size-fits-all answer. They’re also best used in conjunction with other efficient security measures, such as a good Network Firewall.

Network-based, host-based, and cloud-based WAFs have distinct advantages and disadvantages.

WAFs may be deployed in three different ways: network-based, host-based, or cloud-based. Each has pros and cons, so let’s look at each one separately and see how they stack up.

WAFs that are network-based are usually hardware-based. Because they are deployed locally, they have a low latency. They are, however, a costly solution that also requires equipment storage and upkeep.

Host-based WAFs are less expensive than network-based WAFs. It also gives you additional customising possibilities. One of the disadvantages of this sort of WAF is that it consumes local server resources, incurs maintenance expenses, and is difficult to set up.

Cloud-based: This is a cost-effective solution that’s also simple to install. To reroute traffic, it’s usually only a question of changing the DNS. Cloud-based WAFs also offer a cheap upfront cost and a variety of payment choices. These WAFs are regularly updated to assist guard against the latest threats without requiring any effort or money on the part of the user.

The fact that this form of WAF comes from a third-party source limits your customization possibilities and forces you to depend completely on their services.

Let’s go further into HOW a WAF protects your valuable web applications now that we have a fundamental understanding of what it is and the various varieties.

How Do Web Application Firewalls Protect You From Malicious Attacks?

According to Positive Technologies’ 2019 online apps research, hackers may target consumers in 9 out of 10 web applications. Yikes!

Breach of sensitive data was also determined to be a hazard in 68 percent of online apps, according to the survey.

These figures highlight the need for more robust web app security.

WAFs secure your server by monitoring HTTP traffic and identifying and blocking anything harmful BEFORE it reaches your web applications, as previously stated.

WAFs may be network (hardware) based, software-based, or cloud-based, meaning virtual or physical, as we just explained.

When it comes to filtering, detecting, and blocking malicious traffic, WAFs do it in a few different ways…