How to stop wordpress brute force attack

1. Use a strong password

Minimum password recommendations:

- At least 8 characters total
- Mixture of upper and lower-case letters
- Numbers, punctuation or other non-alphanumeric characters

Example weak password: secret1
Improved strong password: Z#hupsZ2M4!Z

2. Change default WordPress admin username

When installing WordPress by default the administrator user has the username of admin.

The botnet attack is currently only targeting this default username, so even having an administrator username of admin123 could signifiantly reduce the likilhood of your site being succesfully logged into by a malicious user.

3. Lock down WordPress admin access with .htaccess

Utilizing a WordPress brute force plugin for this type of attack is not very efficient, and in some cases can actually lead to your site becoming unavailable due to the large amount of processing power used to attempt to challenge each and every malicious login attempt.

Instead you should rely on the information we have on how to lock down WordPress admin login with .htaccess.

Setup a secondary level password to prevent unauthorized WordPress wp-admin and wp-login.php attempts.



4. Temporaily disable CPU intensive login limit plugins

Blocking this attack with .htaccess rules is the preferred method, as login limiting plugins can not only lead to issue with triggering our own internal security rules, but they also will not be effective in this type of large scale attack.

5. Scan website for hacks, check Google Safe Browsing

If your WordPress site had been successfully compromised, a clear indication will usually be found either by a surface security scan of the website, or it will also get reported to Google's Safe Browsing.

Scan your website with an online malware scanner like sitecheck.sucuri.net/scanner

Check Google's safe browsing for your domain, at google.com/safebrowsing/diagnostic?site=example.com

6. Setup CloudFlare DNS level protection

Due to the large scale of this botnet attack, CloudFlare has offered DNS level filtering for this attack on all of their free accounts.

While probably not an ideal solution if you have many WordPress sites due to having to update the name servers for each domain, and then waiting typically 24-36 hours for DNS propagation. Single site owners might benefit greatly from this type of protection which should block the botnet requests from even making it to the server in the first place.

7. Backup WordPress

At this point it's probably a good idea to backup WordPress just in case. That way, as the attacks continue, you're ensured that you always have a good point to restore back to in the event something goes bad.

Backing up your data

    Backup your website files in cPanel
    Backup your database in cPanel

Restoring your data

    Restore your website files in cPanel
    Restore your database in cPanel

8. Update everything WordPress

To protect yourself from any known exploits to WordPress you should update everything related to WordPress:

Necessary updates to make:

    Update WordPress from admin dashboard
    Update WordPress theme
    Update WordPress plugin

9. Clean up hacks

If your website has been the victim of a hack, you can follow my guide on how to reinstall WordPress after a hack for steps on cleaning it up and getting back in business.

10. Other general WordPress recommendations

    Optimizing WordPress with W3 Total Cache plugin
    Log out of WordPress admin dashboard when not in use
    Limit or disable WordPress revisions
    Disable WordPress autosave
    Install and use Better Delete Revision WordPress plugin

Hopefully your WordPress website should be locked down and secure now, which should help prevent our own internal security rules from blocking your own access to your WordPress admin.

If you're blocked out of your own account and were directed to this article via a warning message be sure that you followed step #3 Lock down WordPress admin access with .htaccess in order to regain access.

source : http://www.inmotionhosting.com/support/news/general/wp-login-brute-force-attack