Security Ninja

The free firewall is based on the 8G ruleset, which blocks the most common attack patterns: SQL injection attempts, directory traversal, malicious query strings, and known bad user agents. For a blog, portfolio, or small business site, it covers the basics. We tested it and it works out of the box, blocking standard attack payloads without false positives on normal WordPress traffic.

Where it falls short compared to Wordfence or NinjaFirewall is WordPress-specific awareness. The 8G rules are generic HTTP filtering, not rules tailored to WordPress plugin vulnerabilities or authentication bypasses. Pro adds advanced controls but the core WAF capability stays the same. If you need deeper application-layer rules, Wordfence's free tier actually gives you more WAF depth at zero cost, though with a 30-day rule delay.

Different tools for different priorities. Wordfence has a far more advanced WAF with rules that understand WordPress internals: user sessions, plugin states, nonce validation. Its threat intelligence network covers 5+ million sites. Security Ninja's 8G firewall is simpler but lighter, with near-zero performance impact and instant protection on activation.

On the non-WAF side, Security Ninja's 50+ security tests are more comprehensive than Wordfence's configuration audit. The vulnerability scanner is competitive. Wordfence wins on malware scanning depth and real-time threat feeds. If WAF depth is your priority, go with Wordfence. If you want a quick security audit plus basic firewall protection with minimal resource usage, Security Ninja is the simpler choice.

No. The 8G firewall runs simple regex pattern matches on incoming requests. There is no database scanning on every page load, no external API calls, no learning mode processing. In our testing, the performance impact was negligible, even on shared hosting.

This is one area where Security Ninja genuinely stands out. Wordfence can impact performance during scans and with Live Traffic logging enabled. BulletProof Security operates at the .htaccess level which is fast but can cause configuration conflicts. NinjaFirewall is also lightweight since it hooks in before WordPress loads. If performance is your main concern, Security Ninja and NinjaFirewall are the two lightest options in the WordPress WAF space.

Yes. Since the 8G firewall operates as basic request filtering inside WordPress, it does not conflict with cloud WAFs like Cloudflare or Sucuri that run at the DNS/edge level. You can layer Security Ninja's endpoint protection with an edge WAF for defense-in-depth.

Running it alongside another WordPress security plugin like Wordfence is technically possible but generally not recommended. Two endpoint firewalls processing the same requests adds overhead and can create conflicting block/allow decisions. Pick one for WAF duties and use the other only for its non-WAF features (like Security Ninja's security tests). The security audit and vulnerability scanner work fine regardless of which WAF plugin handles your firewall.

The multi-site licensing is competitive. At $399/yr for 10 sites ($3.33/site/month) or $599/yr for 25 sites with white-label branding ($2/site/month), it undercuts most alternatives on per-site cost. Wordfence charges $149/yr per site even at volume (though they offer bulk discounts for Care/Response tiers). BulletProof Security beats everyone with its $69.95 lifetime license for unlimited sites, but it only works on Apache.

For agencies, the practical question is whether 8G-level protection is enough for your clients. If you are managing brochure sites and small business WordPress installs, it probably is. If your clients run WooCommerce stores or handle sensitive data, you likely want the deeper rules of Wordfence or NinjaFirewall on those sites, with Security Ninja covering the simpler ones.

The 8G Firewall is a set of request filtering rules originally developed by Jeff Starr at Perishable Press. It is the eighth generation of a long-running project that filters malicious HTTP requests based on patterns in the URL, query string, user agent, referrer, and request method. The rules target SQL injection, directory traversal, cross-site scripting, null byte injection, and various bot/spam patterns.

Think of it as a bouncer checking IDs at the door. It does not understand your application, but it knows what suspicious requests look like and blocks them before they get inside. It is battle-tested across millions of sites and rarely causes false positives on legitimate traffic. The tradeoff is that it cannot catch application-specific attacks like WordPress plugin vulnerabilities that use normal-looking requests. For that level of protection, you need a WordPress-aware WAF like Wordfence.