How to Limit Login Attempts in WordPress

WordPress is now the most used platform for building websites but its popularity also makes it a target for malicious actors. Brute-force attacks where bots or attackers try countless username and password combinations are a common threat. Limiting login attempts is an important security measure to protect your WordPress site from unauthorized access and potential damage.

In this article, we will discuss how to limit login attempt limitations in WordPress. We will explore the reasons behind implementing this security measure different methods for achieving it, and the best practices to ensure optimal protection.

Why Limit Login Attempts?

During a brute-force attack on your WordPress login, an attacker performs repeated testing with different keys. By limiting login attempts you will introduce a significant obstacle for attackers. Here’s why it’s essential:

1. Limiting attempts force attackers to exhaust their list much quicker significantly reducing the risk of successful unauthorized logins.
2. Hackers often target specific usernames or emails associated with administrator accounts. Limiting attempts makes it much harder to gain access through these targeted attacks.
3. Constant login attempts can put a load on your server’s resources. Limiting them helps maintain optimal performance for legitimate users.
4. The presence of login attempt limitations itself sends a message to potential attackers that your site is secured potentially stopping them from even attempting an attack.

Methods for Limiting Login Attempts in WordPress

There are three primary approaches to limit login attempts in WordPress:

Implementing Login Attempt Limits with Plugins

Security plugins are the most user-friendly and widely used method for limiting login attempts. Here’s a breakdown of the process:

1. Popular options include Limit Login Attempts Reloaded, Wordfence Security, and Sucuri Security which includes free and premium versions, choosing the plugin according to your preferences.

2. Navigate to the WordPress admin panel, go to the “Plugins” section then “Add New” search for your chosen plugin for example I am using Limit Login Attempts, and click on the Activate button.

3. Each limit login attempts plugin has its own settings page. Look for options related to login attempts. You can typically define:

• Several Allowed Attempts: Set a reasonable limit for failed login attempts before a lockout with a common range is 3 to 5 attempts.
• Lockout Duration: Determine the time a user or IP address will be locked out after exceeding the attempt limit. Options usually range from minutes to hours.
• IP Locking: Choose to limit attempts per user account or per IP address. Limiting by IP helps prevent coordinated attacks.
• Login Form Notifications: Configure messages displayed to users informing them of remaining attempts or lockouts.

When configuring the plugin find a balance between security and user experience. Too few attempts can frustrate legitimate users, while too many can leave your site vulnerable.

Implementing Login Attempt Limits with Editing wp-login file

This method requires editing a core WordPress file and should be attempted with caution. Here’s a simplified overview:

1. Always create a backup of the file before making any modifications. Use an FTP or file manager which in my case cPanel to access the wp-login.php file in your WordPress root directory.

2. You will need to add code to track and limit attempts. Here’s a simplified code snippet that demonstrates the core functionality of limiting login attempts:

<?php
$login_attempts = (int) get_transient( 'login_attempt_count' );
$lockout_duration = 3600;
if ( isset( $_POST['log'] ) && isset( $_POST['pwd'] ) ) {
  $user = wp_authenticate_username_password( null, $_POST['log'] );
  if ( is_wp_error( $user ) ) {
    $login_attempts = ( isset( $login_attempts ) ? $login_attempts + 1 : 1 );
    set_transient( 'login_attempt_count', $login_attempts, $lockout_duration );
    if ( $login_attempts > 3 ) {
      wp_die( __( 'Too many failed login attempts. Please try again later.' ) );
    }
  } else {
    delete_transient( 'login_attempt_count' );
  }
}
?>

3. Save the modified wp-login.php file and upload it back to your server.

Implementing Login Attempt Limits Using .htaccess File

Modifying .htaccess incorrectly can break your website functionality. It’s strongly recommended to consider the plugin or manual wp-login.php editing methods before attempting this approach.

1. Use your FTP client or web hosting control panel file manager to access the .htaccess file located in your WordPress root directory.

2. Ensure the mod_rewrite Apache module is enabled on your server. This module is essential for utilizing the rewrite rules within .htaccess.

3. Add the following code snippet to the beginning of your .htaccess file:

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{REQUEST_URI} ^wp-login.php$ [OR]
RewriteCond %{REQUEST_URI} ^xmlrpc.php$
RewriteRule ^(.*)$ - [F,L]
RewriteRule ^ index.php?action=login_attempt_check&unique_id=%{UNIQUE_ID}&request_time=%{REQUEST_TIME}&limit=3&lockout_duration=3600 [L]
</IfModule>

4. This step requires creating a custom PHP script named index.php within your WordPress root directory you can also use the above login script. The script will need to:

• Access the environment variables containing the unique ID and request timestamp.
• Read a configuration file storing your defined login attempt limit and lockout duration.
• Check the user’s login attempt history using a database or custom logic based on the unique ID or IP address.
• If attempts exceed the limit block access and display a lockout message.
• Otherwise, allow the login attempt to proceed normally.

Integrating with Fail2ban

For a more robust solution, consider integrating Fail2ban which is a server-side tool for blocking IP addresses exhibiting suspicious behavior. You can modify the .htaccess code to send information about exceeding login attempts to Fail2ban, which can then automatically add the IP address to a temporary blacklist.

Important Notes

Following are the important notes on the topic of how to limit login attempts in WordPress:

• Ensure the custom login attempt check script is secure and properly sanitizes user input to avoid vulnerabilities.
• Test the implementation thoroughly on a staging environment before deploying it to your live website.
• Security plugins offer a user-friendly and often more secure approach to limiting login attempts in WordPress.

Conclusion

Limiting login attempts is an important security measure for any WordPress website. By implementing one of the methods discussed in this article and following the best practices, you can significantly reduce the risk of unauthorized access and protect your website from malicious activity.

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