Web Application Firewall

This is a countermeasure. To view all countermeasures, please see the Countermeasure Category page.

Description

A web application firewall (WAF) is an appliance, server plugin, or filter that applies a set of rules to an HTTP conversation. Generally, these rules cover common attacks such as cross-site scripting (XSS) and SQL injection. By customizing the rules to your application, many attacks can be identified and blocked. The effort to perform this customization can be significant and needs to be maintained as the application is modified.

A far more detailed description is available at Wikipedia.

Important selection criteria

For more information on web application firewall evaluation criteria, please visit Web Application Firewall Evaluation Criteria.

Tools

OWASP projects of this type

• https://www.owasp.org/index.php/Category:OWASP_ModSecurity_Core_Rule_Set_Project
• NAXSI is a WAF for NGINX.

Tools Listing

Consider the Web Application Firewall Evaluation Criteria Project (WAFEC) to help evaluate commercial and open source web application firewalls. https://www.owasp.org/index.php/WASC_OWASP_Web_Application_Firewall_Evaluation_Criteria_Project

References

• https://en.wikipedia.org/wiki/Application_firewall
• http://projects.webappsec.org/w/page/13246985/Web%20Application%20Firewall%20Evaluation%20Criteria