Is WordPress safe from brute force login attempts? If not, how can you prevent?

No, WordPress on its own is vulnerable to brute force login attempts.

Some good examples of actions performed to protect a WordPress installation against brute force are:

  • Do not use the “admin” username, and use strong passwords.
  • Password protect “wp-login.php”.
  • Set up some server-side protections (IP-based restrictions, firewall, Apache/Nginx modules, etc.)
  • Install a plugin to add a captcha, or limit login attempts.