How to Secure a Drupal Website Using WAF?

In this interlinked world, web application security has become a shared responsibility of organizations and developers. As Drupal-based applications are becoming more and more popular and complex, it is becoming more and more important to protect sensitive data and application resources. The edge layer, safeguarded by a Web Application Firewall (WAF), serves as a crucial defence layer in Drupal architecture.

Why Use a WAF for Drupal?

Drupal security starts with keeping the core software, modules, and themes updated. However, application updates and WAF protection serve different purposes. A WAF can provide an additional layer of filtering malicious HTTP requests before reaching Drupal.

For instance, a WAF detects suspicious request patterns linked with SQL injection, XSS, malicious bots, and other common web attacks. Depending on the WAF solution you choose to deploy, it provides controls such as rate limiting and traffic filtering.

Step 1: Understand your Drupal Website’s Attack Surface

Before you enable or change WAF rules, identify which part of the Drupal site is public.

Search for login pages, search forms, contact forms, file uploads, APIs, admin paths, user registration, and third-party integrations. Having a clear understanding of entry points enables you to know about the areas that need more protection.

This is crucial because a WAF’s generic rules cannot comprehend the unique business logic of every application. OWASP recommends combining general WAF protections with application-specific rules where appropriate.

Step 2: Choose and Enable a WAF

You deploy a WAF in different ways depending on the web hosting environment. It can run on the web server as a separate infrastructure component or cloud service in front of the origin server.

If your web hosting provider has WAF protection, enable it from the security dashboard. ISolutions like ModSecurity with OWASP Core Rule Set can help reduce the risk of an HTTP attack if you operate your own server. ModSecurity is an open-source web application firewall that can evaluate incoming and outgoing HTTP traffic, according to OWASP.

Step 3: Lock Down the Admin Area

Set the WAF to throttle and log suspicious requests to Drupal’s login and admin areas. Pair this with a strong password and multi-factor authentication for added security.

The administrative section is the most critical, as unauthorized access could allow attackers to modify the website’s content, settings, and overall functionality. They limit repeated login attempts and suspicious traffic, which limits the risks of a brute-force attack on administrator accounts.

Step 4: Enable Rate Limits

Use rate limiting to restrict login attempts on pages, forms, APIs, and other sensitive endpoints. It prevents automated abuse and brute force attacks.

Attackers or malicious bots can send a ton of requests in a small amount of time, exhausting the resources of the server by continually testing out vulnerable endpoints. Reasonable limitations may be set on this activity whilst still allowing for normal visitors to access the website.

Step 5: Build Custom Rules

Create custom WAF rules for specific parts of the Drupal website that need additional shielding. Create the rules as narrowly as possible to exclude illegitimate visitors.

For example, you have an API endpoint, a file upload form, and a customer login page, and you want to have stronger security around them. Focused rules are more accurate than simply setting the whole website with overly restrictive settings.

Step 6. Review WAF Logs

Routinely review WAF logs for blocked requests, recurring attacks, and false positives. If you are blocking legitimate Drupal functionality, change the specific rule rather than disabling the entire WAF.

WAF logs show irregular traffic patterns and repeated attack attempts. Regular reviews enable administrators to identify how attackers target the website and make informed adjustments.

Step 7: Test Your Website

Also, after the WAF configuration test, major functions like login, registration, forms, file uploads, APIs, and e-commerce features.

Ensure security measures don’t negatively affect the website. Change the settings, add new rules, or change the WAF’s security level after which you should then test the website. If a legitimate request fails, look for the rule that protects the website from the attack. It is better to provide a reasonable amount of protection rather than decrease protection for the entire website.

Step 8: Keep Everything Up-to-Date

Drupal core, modules, themes, and WAF rules must be updated regularly. By updating regularly you protect your website from newly discovered security vulnerabilities and attack techniques.

A WAF is an addition to Drupal’s security practices, not a replacement. Keeping CMS and extensions up-to-date reduces known vulnerabilities. Ensuring that the WAF rules are up-to-date helps in protecting from malicious web traffic.