Layer 7 (L7) DDoS attacks target the application layer of websites and web services, attempting to overwhelm servers with HTTP requests that mimic legitimate users. These attacks are harder to detect than network-level attacks and can severely impact website performance. For organizations and startups on a budget, free L7 DDoS protection tools can provide essential defense.

Here are the 10 best free tools in 2025.

1. SafeLine WAF (Free Community Edition)

SafeLine WAF offers a free community edition that provides essential L7 DDoS protection. It features semantic analysis to detect abnormal request patterns, bot detection, and request filtering. Unlike many cloud-only solutions, SafeLine can be self-hosted, giving organizations full control over traffic, rules, and privacy. It’s ideal for startups, labs, and developers seeking a robust, no-cost security solution.

2. Cloudflare Free

Cloudflare’s free tier includes basic web application firewall and DDoS mitigation. It can absorb some Layer 7 traffic and provides rate-limiting rules, although advanced bot management is reserved for paid plans.

3. ModSecurity

ModSecurity is an open-source WAF that integrates with Apache, Nginx, and IIS. It allows custom rule sets and can help mitigate L7 DDoS attacks, SQL injections, and XSS, though setup requires technical expertise.

4. Nginx + Fail2Ban

Using Nginx in combination with Fail2Ban can provide a free solution for mitigating simple L7 DDoS attacks. Fail2Ban monitors logs and blocks IPs showing suspicious behavior.

5. OpenResty + Lua Scripts

OpenResty allows writing Lua scripts to implement request rate limiting and behavioral analysis. While not a plug-and-play WAF, it can be configured to block abusive L7 traffic for free.

6. Cloudbric Free

Cloudbric offers a free tier for small websites, including basic web application firewall and L7 DDoS protection. It provides automated filtering of common malicious traffic.

7. BitNinja Free Trial

BitNinja provides a free trial with protection against Layer 7 attacks, botnets, and other threats. While the trial is time-limited, it’s a good option for testing DDoS defenses.

8. Comodo Free WAF

Comodo offers a free WAF solution for websites, protecting against SQL injection, XSS, and Layer 7 DDoS attacks. It integrates with common web servers and includes basic monitoring.

9. WAF-FLE (Free Lite Edition)

WAF-FLE provides a lightweight, free version of its WAF that helps block malicious L7 requests. It’s suitable for developers needing minimal resource overhead while still protecting web applications.

10. Open Web Application Security Project (OWASP) CRS

The OWASP Core Rule Set (CRS) can be used with ModSecurity or other WAF engines to provide free rules for mitigating L7 attacks. It’s highly customizable and maintained by the security community.

Conclusion

Free L7 DDoS protection tools can provide essential defense for startups, labs, and small businesses.