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Free Plugin by nintechnet v4.9

NinjaFirewall

A true Web Application Firewall to protect and secure WordPress.

NinjaFirewall

The facts

Rating
4.9★ from 220
Active installs
100k+
Price
Free
Last updated
16 Aug 2026
Added
Mar 2013
Requires WP
4.9
Tested up to
WP 7.1
Requires PHP
7.1
Downloads
3,529,688

Our analysis

AI-assisted

NinjaFirewall (WP Edition) is a standalone Web Application Firewall designed for WordPress. It acts as a protective layer in front of your WordPress installation, offering advanced security features that are typically found in dedicated security applications rather than standard plugins.

This plugin is suitable for blog administrators looking for robust security measures against various threats, including brute-force attacks and file modifications. It requires PHP 7.1 and is compatible only with Unix-like operating systems.

Best for: This plugin suits WordPress site administrators needing advanced security features.

What it does well

  • Standalone firewall for enhanced security
  • Powerful filtering engine for detecting evasion techniques
  • Real-time detection of file modifications
  • Brute-force attack protection for wp-login.php and xmlrpc.php
  • File integrity monitoring with regular scans

Where it falls short

  • Not compatible with Microsoft Windows
  • Requires specific server configurations (PHP 7.1, MySQLi)

Verdict

NinjaFirewall (WP Edition) offers strong security capabilities for WordPress users, especially those on Unix-like systems. It is a solid choice for those prioritising website protection.

From the developer

nintechnet's own description of NinjaFirewall, lightly tidied.

A true Web Application Firewall

NinjaFirewall (WP Edition) is a true Web Application Firewall. Although it can be installed and configured just like a plugin, it is a stand-alone firewall that stands in front of WordPress.

It allows any blog administrator to benefit from very advanced and powerful security features that usually aren’t available at the WordPress level, but only in security applications such as the Apache ModSecurity module or the PHP Suhosin extension.

NinjaFirewall requires at least PHP 7.1, MySQLi extension and is only compatible with Unix-like OS (Linux, BSD). It is not compatible with Microsoft Windows.

NinjaFirewall can hook, scan, sanitise or reject any HTTP/HTTPS request sent to a PHP script before it reaches WordPress or any of its plugins. All scripts located inside the blog installation directories and sub-directories will be protected, including those that aren’t part of the WordPress package. Even encoded PHP scripts, hackers shell scripts and backdoors will be filtered by NinjaFirewall.

Powerful filtering engine

NinjaFirewall includes the most powerful filtering engine available in a WordPress plugin. Its most important feature is its ability to normalize and transform data from incoming HTTP requests which allows it to detect Web Application Firewall evasion techniques and obfuscation tactics used by hackers, as well as to support and decode a large set of encodings. See our blog for a full description: An introduction to NinjaFirewall filtering engine.

Fastest and most efficient brute-force attack protection for WordPress

By processing incoming HTTP requests before your blog and any of its plugins, NinjaFirewall is the only plugin for WordPress able to protect it against very large brute-force attacks, including distributed attacks coming from several thousands of different IPs.

See our benchmarks and stress-tests: Brute-force attack detection plugins comparison

The protection applies to the wp-login.php script but can be extended to the xmlrpc.php one. The incident can also be written to the server AUTH log, which can be useful to the system administrator for monitoring purposes or banning IPs at the server level (e.g., Fail2ban).

Real-time detection

File Guard real-time detection is a totally unique feature provided by NinjaFirewall: it can detect, in real-time, any access to a PHP file that was recently modified or created, and alert you about this. If a hacker uploaded a shell script to your site (or injected a backdoor into an already existing file) and tried to directly access that file using his browser or a script, NinjaFirewall would hook the HTTP request and immediately detect that the file was recently modified or created. It would send you an alert with all details (script name, IP, request, date and time).

File integrity monitoring

File Check lets you perform file integrity monitoring by scanning your website hourly, twicedaily or daily. Any modification made to a file will be detected: file content, file permissions, file ownership, timestamp as well as file creation and deletion.

Watch your website traffic in real time

Read the full description on the official page →

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