How Web Application Firewalls Protect Against Common Threats

Despite organizations’ best efforts, cyberthreats are more prevalent than ever. The most common threats are becoming more dangerous for your data and more difficult to fix, which means you need to invest in a solution that can catch attacks early. The best way to mitigate damage is to prevent it.

Implementing a Web Application Firewall (WAF) is one of the simplest ways to prevent attack. WAFs act as a barrier and filter between your web application or API and the rest of the Internet, which reduces your risk of a security incident. Because security issues can lead to compliance violations or customer avoidance, it’s important to establish an initial barrier between you and the Internet as soon as possible.

Protecting your organization with a WAF won’t guarantee perfect security, but it can help manage traffic and prevent crises down the road.

What is a WAF?

A Web Application Firewall, or WAF, takes the protection capabilities of a traditional firewall and applies them to the online space. Traditional firewalls have long been used to protect on-site devices from attack, but they are impractical for businesses that rely on the cloud to host data and web applications. WAFs are typically cloud-based firewall solutions that filter and block online traffic, and because they are cloud solutions, they can be implemented across multiple off-site servers, applications, and APIs.

Cyberthreats are everywhere, but WAFs keep them out of your environment, much like a fence around a physical asset. As with any firewall, you are able to create rules to distinguish between legitimate and illegitimate traffic. By combining automated monitoring capabilities with these traffic filters, WAFs block unauthorized access attempts and bots without disrupting the traffic you want on your web apps and APIs.

More adaptable than traditional firewalls, WAFs can be trained to identify advanced bots and evolving threats, and they fully integrate with your web applications to protect your data from malicious actors and improper access and exfiltration. An effective WAF will also include alert features that keep you up to date with threats to your security.

Common Threats Web Application Firewalls Protect Against

There are several common threats to web applications, which are explained in greater detail by OWASP. The OWASP Top 10 describes the threats that pose the greatest risk to your organization, whether because they are common or because they are severe.

A few examples of OWASP threats and how WAFs can help are listed here:

• Broken Access Control. This is a privilege problem. Most users have limited privilege, and this threat expands user access so that an unauthorized user can access a larger amount of data. WAFs mitigate this by alerting you to unusual activity and enforcing access controls based on the rules you have set.
• Insecure Design: Developers do not always successfully release secure applications, and they don’t always operate with security in mind. Since you don’t know what you don’t know, implementing a WAF as a first line of defense is one of the best ways to prevent attackers from exploiting built-in vulnerabilities.
• Cryptographic Failure. Encryption is an essential part of a secure web app or API, and failure to implement effective encryption exposes your data to unauthorized access.
• Authentication Failure. If an attacker compromises credentials or attempts to break into a user’s account, the WAF can detect atypical behavior through fingerprinting. Fingerprinting tracks typical device or browser behavior, allowing WAFs to establish a baseline and recognize deviations. Web scraping attacks are mitigated this way.

While this is not an exhaustive list of the common threats WAFs mitigate, these are top concerns for your organization. WAFs also protect against SQL injection, DDoS, and XSS attacks. Generally, a WAF can help with any threat that uses HTTPS requests as attack vectors as built-in rules and machine learning can quickly identify attack patterns in these requests and will block them.

Benefits of Implementing a Web Application Firewall

Some of today’s cyberthreats may seem a bit esoteric, but preventing them is important for protecting data security and ensuring service availability. For regions with strict data security laws, WAFs can also help you with compliance (in some regions, WAFs are actually required by law in your environment).

The right WAF should have a few benefits that will maximize your security, including:

• Automated monitoring and alerts. Simple blocking is great, but you want to be proactive about your security. Knowing what you’re dealing with is essential.
• Low false positives. Blocking legitimate traffic would be damaging to your reputation and your ability to serve customers.
• Automated policy creation and machine learning capabilities. Reacting on your own to threats and reports of threats is likely to be somewhat slow. Automation that allows the WAF to update itself means faster turnaround time and less risk of a successful attack.
• Dynamic profiling: Your WAF solution needs to be able to learn in real time. It should be able to utilize fingerprinting, rules, and behavior analysis to determine whether to block traffic or not.
• DDoS protection. You don’t want your website going down, so you’ll need a WAF solution that can handle sudden traffic increases and blocking DDoS attacks.

Partly due to their online nature, web applications have many potential attack vectors. Web apps often contain exploitable vulnerabilities because they are often built with open-source code that is publicly available, which means that attackers can study it and find ways into your web apps and APIs. However, you can make this much more difficult for them by implementing a WAF.

Although a WAF does not address the vulnerabilities themselves, it provides a first line of defense against attack by preventing unauthorized access and restricting the malicious traffic. If you have a web app, even if you think your patching game is pretty good, you should also have a WAF that is built to respond and adapt to changing cyberthreats. After all, it’s more cost-effective to invest in protective measures than disaster recovery strategies.