The Role of WAFs in Protecting Against Zero-Day Exploits

Malicious traffic is a part of online life, but that doesn’t mean you want it anywhere near your applications, especially if your applications have unknown vulnerabilities (they often do). These unknown vulnerabilities, or zero-day vulnerabilities, are especially risky for organizations because it is nearly impossible to prepare for them in advance.

The risks are growing. Attackers are becoming more sophisticated every day, which means it’s likely only a matter of time before they find any of these zero-day vulnerabilities if your application is unprotected. This is where a WAF, or Web Application Firewall, is beneficial. Acting as a barrier between your vulnerabilities and malicious traffic, the WAF limits your risk of exploitation by keeping bad traffic out of your environment.

The Growing Threat Landscape of Zero-Day Vulnerabilities

Web application and network attacks are nothing new, but they are becoming increasingly complex. Botnets are growing in size with the growing popularity of IoT devices, and attacks are easier than ever to launch with the advent of areas like DDoS as a Service. The bots themselves are far more evasive than they have been in the past, often slipping by defenses by mimicking typical human and authorized user behavior.

And that’s just the attackers. An additional challenge for security teams is the openings in an application that these attackers will target. Vulnerabilities are everywhere in any given software, but security teams are generally able to address these through updates and patches if they are not caught during development. However, they usually don’t catch all of the potential vulnerabilities.

The growth of open-source software has made it easier for attackers to find weak spots in code. The code upon which many applications are built is widely available, and the tools that someone can use to find vulnerabilities are increasingly complex. Some attackers have begun using AI to find weaknesses, and combined with more sophisticated attack methods, security teams are struggling to keep up.

Given these conditions, potential zero-day attacks and vulnerabilities are everywhere. These unknowns are an enormous risk for organizations. If no one sees the attack coming, recovery is especially challenging.

Where WAFs Come into Play

To help address these issues, many organizations have turned to WAFs that can be used to block attacks against vulnerable systems. Because zero-day vulnerabilities are typically unknown to an organization’s security and development teams, it’s very difficult to prepare for a particular attack. WAFs provide a blanket of protection around a network, ensuring that any vulnerabilities within an application are secured, even if security teams don’t know what or where those weaknesses are.

The average WAF does well with keeping threats away from zero-day vulnerabilities, but security professionals ought not forget about unknown attacks. While a traditional WAF does its best work blocking known activity patterns, a more sophisticated solution is needed to make sure that both attacks and vulnerabilities are adequately protected. A WAF with advanced detection tools that are based on machine learning threat intelligence is the best way to go.

Managing Zero-Day Threats with WAFs

With traditional solutions, it’s a fairly simple task to create firewall rules and customizations that prevent known attacks from reaching your network. However, older solutions cannot effectively detect and block zero-day attacks, especially if those attacks are launched from highly sophisticated and evasive bots.

Zero-day attacks come with a host of risks. Like any other attack, they can compromise your data and infrastructure. They can cause downtime and revenue losses for your organization, and under certain conditions, they may cause you to become non-compliant with data privacy regulations. Exploiting a zero-day vulnerability in your application gives attackers access to your infrastructure and data as well.

These risks are amplified by the fact that zero-day attacks are much more challenging to detect than known attacks. When a known pattern of traffic is acting on your network, a traditional WAF will be able to detect and block it based on your predetermined rules. However, a novel attack does not necessarily match the rules you have set up, which could allow the attack to evade the WAF.

To prevent this problem and eliminate weaknesses in organizational security, cloud-based WAFs are now available with AI and machine learning components. By leveraging these tools, the modern WAF can adapt in real-time to zero-day attacks, which has two essential consequences:

●Higher sensitivity to malicious traffic. Traditional WAFs tend to miss zero-day attacks. They rely on the rules your security teams have set, and they are unable to discern new kinds of attacks in many cases. In contrast, the modern WAF is able to use context and pattern recognition to catch them.

●Improved incident responses. Rather than requiring your security teams to jump on every alert, a modern WAF can change its rules on its own. By adapting to potentially dangerous traffic without human intervention, the WAF decreases the resources needed to handle an incoming zero-day attack. Faster response times ultimately result in less damage to infrastructure and prevent unauthorized access to data.

Implementing a modern WAF is an important part of protecting your network and applications from zero-day exploits and vulnerabilities. While a traditional WAF has been useful in the past for detecting known attacks, zero-day detection has typically been the domain of other tools.

The modern WAF deters threats from outside your network while insulating weaknesses within. One of the greatest risks to a business is threats that its security teams don’t see coming, which is the danger of zero-day exploits. The growing numbers and sophistication of bots and other cyberthreats, as well as the growing difficulty of keeping up with attackers finding code vulnerabilities, make it essential for organizations to leverage as many protective measures as possible.