AWS WAF (Web Application Firewall)

AWS WAF is a web application firewall that helps protect your web applications from common web exploits that could affect application availability, compromise security, or consume excessive resources. It provides customizable rules to block, allow, or count web requests based on conditions such as IP addresses, HTTP headers, and query string parameters.

Key Features

• Customizable Rules: Define rules to match specific patterns in web requests, such as IP addresses, HTTP headers, URIs, and query string parameters.
• Managed Rule Groups: Use pre-configured managed rule groups provided by AWS or AWS Marketplace to protect against common threats like SQL injection and cross-site scripting (XSS).
• Real-Time Metrics and Logging: Monitor web traffic and analyze request patterns with real-time metrics and detailed logging via Amazon CloudWatch and AWS Kinesis Data Firehose.
• IP Set and Regex Pattern Set: Create IP sets to allow or block requests from specific IP addresses and regex pattern sets to match complex request patterns.
• Integration with AWS Services: Integrate with other AWS services like AWS Shield for DDoS protection, Amazon CloudFront for content delivery, and Application Load Balancer (ALB) for routing traffic.

Common Use Cases

• Protecting Web Applications: Safeguard your web applications from common vulnerabilities and attacks, such as SQL injection, XSS, and HTTP flood attacks.
• Regulatory Compliance: Implement security measures to meet compliance requirements and protect sensitive data by filtering malicious web traffic.
• Rate Limiting: Control the rate of incoming requests to your application to prevent abuse and ensure fair access for all users.
• Bot Protection: Block or challenge requests from known malicious bots and automated scripts to prevent scraping and other automated attacks.

Architecture Overview

The following diagram illustrates how AWS WAF integrates with other AWS services to provide web application protection:

• Web ACL: Create and manage web access control lists (ACLs) that define the rules for filtering web requests.
• Rules and Conditions: Configure rules and conditions to match specific request patterns and apply actions (allow, block, count).
• Integration Points: Attach web ACLs to resources like Amazon CloudFront distributions, Application Load Balancers (ALBs), and AWS API Gateway APIs.
• Monitoring and Logging: Use CloudWatch metrics and Kinesis Data Firehose for real-time monitoring and logging of web traffic.

Integration with Other AWS Services

AWS WAF integrates with various AWS services to enhance security and provide comprehensive protection:

• Amazon CloudFront: Apply WAF rules to CloudFront distributions to protect your content delivery network (CDN) from malicious requests.
• Application Load Balancer (ALB): Attach WAF web ACLs to ALBs to filter traffic to your application instances based on custom rules.
• AWS API Gateway: Protect APIs from malicious traffic and attacks by applying WAF rules to your API Gateway endpoints.
• AWS Shield: Integrate with AWS Shield for additional DDoS protection and enhanced security for your web applications.
• Amazon CloudWatch: Monitor web traffic and WAF metrics with CloudWatch dashboards and alarms for proactive security management.

Things to Remember for the Exam

• WAF Rules and Conditions: Understand how to create and configure WAF rules and conditions, including IP set and regex pattern set usage.
• Managed Rule Groups: Familiarize yourself with AWS managed rule groups and third-party options for common web security threats.
• Web ACL Configuration: Review how to configure web ACLs and associate them with AWS resources such as CloudFront distributions and ALBs.
• Integration Points: Know the integration points with other AWS services and how WAF can be used in conjunction with services like AWS Shield and CloudWatch.
• Metrics and Logging: Understand how to set up and interpret CloudWatch metrics and Kinesis Data Firehose logs for WAF monitoring and analysis.
• Rate Limiting and Bot Protection: Review how to configure rate limiting and bot protection features to prevent abuse and automated attacks.