Carlos

In many WordPress installations is possible enumerate usernames through the author archives, using urls like this:
http://wpsite/?author=1
http://wpsite/?author=1/
http://wpsite/?bypass=1&author%00=1
http://wpsite/?author%00=%001
http://wpsite/?%61uthor=1
And recently wordpress since 4.7 comes with a rest api integrated that allow list users:
curl -s http://wpsite/wp-json/wp/v2/users/ 
curl -s http://wpsite/?rest_route=/wp/v2/users 
curl http://wpsite/?_method=GET -d rest_route=/wp/v2/users
Know the username of a administrator is the half battle, now an attacker only need guest the password. 
This plugin stop it.
Also, is possible get usernames from the post entries. 
This plugin, hide the name of the author in a post entry if he is not using a nickname. 
Also, hide the url page link of an administrator author.
The main goal is hide the administrators usernames. 
Obviously, is better not choose “admin” as the username because is easiliy guessable.

No User Enumeration

Khushal Tank

Khushal Login Path Guard is a WordPress security plugin that allows you to change your default login URL and protect your site from common attack vectors. The plugin blocks brute-force attempts, prevents user enumeration, secures sensitive files, and hides WordPress information from potential attackers. All blocked paths display 404 errors (Stealth Mode) instead of redirects, making your site invisible to attackers.
<h4>Features</h4>
Login Protection: 
* Blocks 17+ common brute-force login paths 
* Custom login URL (only you know the path) 
* Shows 404 error instead of redirect (no hints to attackers) 
* Protects /wp-admin, /login, /wp-login.php and more
Advanced Security: 
* Blocks XML-RPC (prevents brute-force via API) 
* Prevents user enumeration via REST API 
* Blocks author page enumeration (?author=1) 
* Protects wp-config.php and sensitive files 
* Blocks direct access to wp-includes PHP files 
* Removes WordPress version information
Security Headers: 
* X-Frame-Options (prevents clickjacking) 
* X-Content-Type-Options (prevents MIME sniffing) 
* X-XSS-Protection (XSS attack protection) 
* Referrer-Policy (privacy protection) 
* Permissions-Policy (feature restriction)
User-Friendly: 
* Easy settings interface 
* One-click URL copy 
* Normal functionality for logged-in users 
* Does not block AJAX requests 
* Clean admin interface
<h4>Security Benefits</h4>
<ol>
<li>Brute Force Protection – 15+ login paths blocked</li>
<li>XML-RPC Disabled – Prevents API-based attacks</li>
<li>User Enumeration Blocked – Hides usernames from attackers</li>
<li>Sensitive Files Protected – wp-config.php, .htaccess secured</li>
<li>Security Headers – Industry-standard HTTP headers</li>
<li>WordPress Hidden – Removes version and generator tags</li>
</ol>
<h4>इस्तेमाल करना बेहद आसान है</h4>
<ol>
<li>Plugin activate करें</li>
<li>Settings > Login Path Security में जाएं</li>
<li>अपना custom login path enter करें</li>
<li>Settings save करें</li>
<li>नया login URL use करें</li>
</ol>

Khushal Login Path Guard

Change your WordPress login URL and protect your site from brute-force attacks. Blocks default login paths with 404 errors.

No User Enumeration vs Khushal Login Path Guard