In a digital environment where web applications are the core of business operations, web system security has become a critical priority. Application-level attacks—such as SQL injections, XSS, or the exploitation of vulnerabilities listed in the OWASP Top 10 guide—remain a leading cause of security breaches.
In this context, WAFs (Web Application Firewalls) play a key role as a specialized defense layer dedicated to detecting cyberattacks against websites.
What is a Web Application Firewall?
A WAF is a security solution designed to monitor, filter, and block malicious HTTP/HTTPS traffic directed at web applications. Unlike traditional firewalls that operate at the network level, a WAF analyzes the content and behavior of requests, enabling the detection of specific Layer 7 attacks.
WAFs can be implemented as:
- Cloud-based solutions
- Physical appliances
- Software or containers
- Managed services
Why are WAFs essential for web security?
Modern web applications are constantly exposed to the Internet, APIs, microservices, and untrusted users. This significantly expands the attack surface. A WAF allows you to:
- Mitigate known and Zero-Day vulnerabilities.
- Protect against automated attacks and malicious bots.
- Reduce the risk of data leaks.
- Comply with security regulations (PCI-DSS, ISO 27001, etc.).
- Protect applications that cannot be easily modified.
In many cases, a WAF acts as the last line of defense when a vulnerability has not yet been patched.
Main threats a WAF can stop
A well-configured WAF helps protect against common threats such as:
- SQL Injection
- Cross-Site Scripting (XSS)
- Cross-Site Request Forgery (CSRF)
- Remote File Inclusion (RFI)
- Brute Force attacks
- Application-layer DDoS
- API Abuse
These threats are part of the OWASP Top 10, reinforcing the importance of having this technology in any modern web architecture.
