When it comes to WordPress security, there are a lot of things you can do to lock down your site to prevent hackers and vulnerabilities from affecting your ecommerce site or blog. The last thing you want to happen is to wake up one morning to discover your site in shambles. So today we are going to be sharing a lot of tips, strategies, and techniques you can use to better your WordPress security and stay protected.

If you’re a Kinsta client, you don’t need to worry about a lot of these, as we offer free hack fixes! But even with this guarantee, you should always follow the best security practices.

Is WordPress Secure?

The first question you’re probably wondering, is WordPress secure? For the most part, yes. However, WordPress usually gets a bad rap for being prone to security vulnerabilities and inherently not being a safe platform to use for a business. More often than not this is due to the fact that users keep following industry-proven security worst-practices.

Using outdated WordPress software, nulled plugins, poor system administration, credentials management, and lack of necessary Web and security knowledge among non-techie WordPress users keep hackers on top of their cyber-crime game. Even industry leaders don’t always use the best practices. Reuters was hacked because they were using an outdated version of WordPress.

Fundamentally, security is not about perfectly secure systems. Such a thing might well be impractical, or impossible to find and/or maintain. What security is though is risk reduction, not risk elimination. It’s about employing all the appropriate controls available to you, within reason, that allow you to improve your overall posture reducing the odds of making yourself a target, subsequently getting hacked. – WordPress Security Codex

Now, this is not to say vulnerabilities don’t exist. According to a Q3 2017 study by Sucuri, a multi-platform security company, WordPress continues to lead the infected websites they worked on (at 83%). This is up from 74% in 2016.

WordPress security vulnerabilities
WordPress security vulnerabilities

WordPress powers over 42.7% of all websites on the internet, and with hundreds of thousands of theme and plugin combinations out there, it’s not surprising that vulnerabilities exist and are constantly being discovered. However, there is also a great community around the WordPress platform, to ensure these things get patched ASAP. The WordPress security team is made up of approximately 50 (up from 25 in 2017) experts including lead developers and security researchers — about half are employees of Automattic and a number work in the web security field.

WordPress Vulnerabilities

Check out some of the different types of WordPress security vulnerabilities below.

Backdoors

The aptly named backdoor vulnerability provides hackers with hidden passages bypassing security encryption to gain access to WordPress websites via abnormal methods – wp-Admin, SFTP, FTP, etc. Once exploited, backdoors enable hackers to wreak havoc on hosting servers with cross-site contamination attacks – compromising multiple sites hosted on the same server. In Q3 2017 Sucuri reported that backdoors continue to be one of the many post-hack actions attackers take, with 71% of the infected sites having some form of backdoor injection.

Malware family distribution
Malware family distribution

Backdoors are often encrypted to appear like legitimate WordPress system files, and make their way through to WordPress databases by exploiting weaknesses and bugs in outdated versions of the platform. The TimThumb fiasco was a prime example of backdoor vulnerability exploiting shady scripts and outdated software compromising millions of websites.

Fortunately, prevention and cure of this vulnerability is fairly simple. You can scan your WordPress site with tools like SiteCheck which can easily detect common backdoors. Two-factor authentication, blocking IPs, restricting admin access and preventing unauthorized execution of PHP files easily takes care of common backdoor threats, which we will go into more below. Canton Becker also has a great post on cleaning up the backdoor mess on your WordPress installations.

Pharma Hacks

The Pharma Hack exploit is used to insert rogue code in outdated versions of WordPress websites and plugins, causing search engines to return ads for pharmaceutical products when a compromised website searched for. The vulnerability is more of a spam menace than traditional malware, but gives search engines enough reason to block the site on accusations of distributing spam.

Moving parts of a Pharma Hack include backdoors in plugins and databases, which can be cleaned up following the instructions from this Sucuri blog. However, the exploits are often vicious variants of encrypted malicious injections hidden in databases and require a thorough clean-up process to fix the vulnerability. Nevertheless, you can easily prevent Pharma Hacks by using recommend WordPress hosting providers with up to date servers and regularly updating your WordPress installations, themes, and plugins. Hosts like Kinsta also offer free hack fixes.

Brute-force Login Attempts

Brute-force login attempts use automated scripts to exploit weak passwords and gain access to your site. Two-step authentication, limiting login attempts, monitoring unauthorized logins, blocking IPs and using strong passwords are some of the easiest and highly effective ways to prevent brute-force attacks. But unfortunately, a number of WordPress website owners fail to perform these security practices whereas hackers are easily able to compromise as much as 30,000 websites in a single day using brute-force attacks.

Malicious Redirects

Malicious redirects create backdoors in WordPress installations using FTP, SFTP, wp-admin, and other protocols and inject redirection codes into the website. The redirects are often placed in your .htaccess file and other WordPress core files in encoded forms, directing the web traffic to malicious sites. We will go through some ways you can prevent these in our WordPress security steps below.

Cross-Site Scripting (XSS)

Cross-Site Scripting (XSS) is when a malicious script is injected into a trusted website or application. The attacker uses this to send malicious code, typically browser-side scripts, to the end user without them knowing it. The purpose is usually to grab cookie or session data or perhaps even rewrite HTML on a page.

According to WordFence, Cross-Site Scripting vulnerabilities are the most common vulnerability found in WordPress plugins by a significant margin.

Denial of Service

Perhaps the most dangerous of them all, Denial of Service (DoS) vulnerability exploits errors and bugs in the code to overwhelm the memory of website operating systems. Hackers have compromised millions of websites and raked in millions of dollars by exploiting outdated and buggy versions of WordPress software with DoS attacks. Although financially motivated cybercriminals are less likely to target small companies, they tend to compromise outdated vulnerable websites in creating botnet chains to attack large businesses.

Even the latest versions of WordPress software cannot comprehensively defend against high-profile DoS attacks, but will at least help you to avoid getting caught in the crossfire between financial institutions and sophisticated cybercriminals. And don’t forget about October 21st, 2016. This was the day the internet went down due to a DNS DDoS attack. Read more about why it is important to use a premium DNS provider to increase your WordPress security.

WordPress Security Guide

According to internet live stats over 100,000 websites are hacked every day. 😮 That’s why it’s so important to take some time and go through the following recommendations below on how to better harden your WordPress security.

WordPress sites hacked every day
WordPress sites hacked every day

We will make sure to keep this post up to date with relevant information as things change with the WordPress platform and new vulnerabilities emerge.

  1. Secure WordPress Hosting
  2. Use Latest PHP Version
  3. Clever Usernames and Passwords
  4. Latest Versions
  5. Lock Down WordPress Admin
  6. Two-Factor Authentication
  7. HTTPS – SSL Certificate
  8. Hardening wp-config.php
  9. Disable XML-RPC
  10. Hide WordPress Version
  11. HTTP Security Headers
  12. WordPress Security Plugins
  13. Database Security
  14. Secure Connections
  15. File and Server Permissions
  16. Disable Editing in Dashboard
  17. Prevent Hotlinking
  18. Always Take WordPress Backups
  19. DDoS Protection

1. Invest in Secure WordPress Hosting

When it comes to WordPress security, there is much more than just locking down your site, although we’ll give you the best recommendations on how to do that below. There is also web server-level security for which your WordPress host is responsible. We take security very seriously here at Kinsta and handle a lot of these issues for our clients.

It’s very important that you choose a host that you can trust with your business. Or if you are hosting WordPress on your own VPS, then you need to have the technical knowledge to do these things yourself. And to be honest, trying to be a sysadmin to save $20/month is a bad idea.

Secure WordPress hosting
Secure WordPress hosting

Server hardening is the key to maintaining a thoroughly-secure WordPress environment. It takes multiple layers of hardware and software level security measures to ensure the IT infrastructure hosting WordPress sites is capable of defending against sophisticated threats, both physical and virtual.

For this reason, servers hosting WordPress should be updated with the latest operating system and (security) software as well as thoroughly tested and scanned for vulnerabilities and malware. A good example of this is when Kinsta had to patch NGINX for OpenSSL security vulnerabilities that were discovered.

Server-level firewalls and intrusion detection systems should be in place before installing WordPress on the server to keep it well-protected even during the WordPress installation and website construction phases. However, every software installed on the machine intended to protect WordPress content should be compatible with the latest database management systems to maintain optimal performance. The server should also be configured to use secure networking and file transfer encryption protocols (such as SFTP instead of FTP) to hide away sensitive content from malicious intruders.

Here at Kinsta, we use Google Cloud Platform’s fastest servers and premium tier network for all of our WordPress customers to ensure a fast and secure WordPress hosting experience. A big advantage of this is that it is built on a security model that has been built upon over the course of 15 years, and currently secures products and services like Gmail, Search, etc. Google currently employs more than 500 full-time security professionals. All sites on Kinsta are also protected by our free Cloudflare integration, which includes a secure enterprise-level firewall as well as free DDoS protection.

Kinsta also uses Linux containers (LXC), and LXD to orchestrate them, on top of Google Cloud Platform which enables us to completely isolate not just each account, but each separate WordPress site. Security is built into our architecture from the beginning and this is a much more secure method than offered by other competitors.

Kinsta hosting architecture.
Kinsta hosting architecture.

2. Use Latest PHP Version

PHP is the backbone of your WordPress site and so using the latest version on your server is very important. Each major release of PHP is typically fully supported for two years after its release. During that time, bugs and security issues are fixed and patch on a regular basis. As of right now, anyone running on version PHP 7.1 or below no longer has security support and are exposed to unpatched security vulnerabilities.

Supported PHP Versions
Supported PHP Versions

And guess what? According to the official WordPress Stats page, as of writing this, over 57% of WordPress users are still on PHP 5.6 or lower. If you combine this with PHP 7.0, a whopping 77.5% of users are currently using PHP versions that is no longer supported. That is scary!

Sometimes it does take businesses and developers time to test and ensure compatibility with their code, but they have no excuse to run on something without security support. Not to mention the huge performance impact running on older versions has.

WordPress PHP version Stats
WordPress PHP version Stats

Don’t know which version of PHP you are currently on? Most hosts typically include this in a header request on your site. A quick way to check is to run your site through Pingdom. Click into the first request and look for a X-Powered-By parameter. Typically this will show the version of PHP your web server is currently using. However, some hosts will remove this header due to security reasons. Kinsta removes this header by default to keep your site safe.

Check PHP version in Pingdom
Check PHP version in Pingdom

Here at Kinsta we only recommend using stable and supported versions of PHP, including 8.0 and 8.1. PHP 5.6, 7.0, and 7.1 have been phased out. You can even switch between PHP versions with a click of a button from within the MyKinsta dashboard.

Switching between PHP versions in MyKinsta
Switching between PHP versions

If you are on a WordPress host that uses cPanel, you can usually switch between PHP versions by clicking into “PHP Select” under the software category.

cpanel php version
cPanel PHP version

3. Use Clever Usernames and Passwords

Surprisingly one of the best ways to harden your WordPress security is to simply use clever usernames and passwords. Sounds pretty easy right? Well, check out SplashData’s 2019 annual list of the most popular passwords stolen throughout the year (sorted in order of popularity).

  • 123456
  • password
  • 123456789
  • 12345678
  • 12345
  • 111111
  • 1234567
  • sunshine
  • qwerty
  • iloveyou

That is right! The most popular password is “123456”, followed by an astonishing “password”. That is one reason why here at Kinsta on new WordPress installs we actually force a complex password to be used for your wp-admin login (as seen below on our one-click install process). This is not optional.

Force secure WordPress password
Force secure WordPress password

The core WordPress wp_hash_password function uses the phpass password hashing framework and eight passes of MD5-based hashing.

Some of the best security starts from the basics. Google has some great recommendations on how to choose a strong password. Or you can use an online tool like Strong Password Generator. You can learn more about here how you can change your WordPress password.

It is also important to use different passwords for every website. The best way to store them is locally in an encrypted database on your computer. A good free tool for this is KeePass. If you don’t want to go down this route there are also online password managers such as 1Password or LastPass. Even though your data is hosted securely in the cloud, these are generally safer since you aren’t using the same password across multiple sites. It also keeps you from using sticky notes. 😉

And as far as your WordPress install goes you should never use the default “admin” username. Create a unique WordPress username for the administrator account and delete the “admin” user if it exists. You can do this by adding a new user under “Users” in the dashboard and assigning it the “Administrator” profile (as seen below).

WordPress administrator role
WordPress administrator role

Once you assign the new account the administrator role you can go back and delete the original “Admin” user. Make sure that when you click on delete that you choose the “Attribute all content to” option and select your new administrator profile. This will assign the person as the author of those posts.

delete admin attribute all content to
Attribute all content to admin

You can also rename your current admin username manually in phpMyAdmin with the following command. Make sure to backup your database before editing tables.

UPDATE wp_users SET user_login = 'newcomplexadminuser' WHERE user_login = 'admin';

4. Always Use the Latest Version of WordPress, Plugins, and Themes

Another very important way to harden your WordPress security is to always keep it up to date. This includes WordPress core, plugins, and themes (both those from the WordPress repository and premium). These are updated for a reason, and a lot of times these include security enhancements and bug fixes. We recommend you to read our in-depth guide on how WordPress automatic updates work.

Keep WordPress up to date
Keep WordPress up to date

Unfortunately, millions of businesses out there running outdated versions of WordPress software and plugins, and still believe they’re on the right path of business success. They cite reasons for not updating such as “their site will break” or “core modifications will be gone” or “plugin X won’t work” or “they just don’t need the new functionality”.

In fact, websites break mostly because of bugs in older WordPress versions. Core modifications are never recommended by the WordPress team and expert developers who understand the risks involved. And WordPress updates mostly include must-have security patches along with the added functionality required to run the latest plugins.

Did you know that it has been reported that plugin vulnerabilities represent 55.9% of the known entry points for hackers? That is what WordFence found in a study where they interviewed over 1,000 WordPress site owners that had been victims of attacks. By updating your plugins you can better ensure that you aren’t one of these victims.

hacked wordpress websites plugins
Hacked WordPress sites

It is also recommended that you only install trusted plugins. The “featured” and “popular” categories in the WordPress repository can be a good place to start. Or download it directly from the developer’s website. We strongly discourage any use of nulled WordPress plugins and themes.

First off, you never know what the modified code might contain. This can easily end up in your site getting hacked. Not paying for premium WordPress plugins also doesn’t help the community grow as a whole. We need to support developers.

Here’s how to properly delete a WordPress theme.

You can use an online tool like VirusTotal to scan a plugin or theme’s files to see if it detects any type of malware.

VirusTotal
VirusTotal

How to Update WordPress Core

There are a couple easy ways to update your WordPress installation. If you are a Kinsta customer we provided automatic backups with a one-click restore option. This way you can test new versions of WordPress and plugins without having to worry about it breaking anything. Or you could also first test in our staging environment.

To update WordPress core you can click into “Updates” in your WordPress dashboard and click on the “Update Now” button.

Update WordPress core
Update WordPress core

You can also update WordPress manually by downloading the latest version and uploading it via SFTP.

Important! Overwriting the wrong folders could break your site if not done correctly. If you are not comfortable doing this, please check with a developer first.

Follow the steps below to update your existing installation:

  1. Delete the old wp-includes and wp-admin directories.
  2. Upload the new wp-includes and wp-admin directories.
  3. Upload the individual files from the new wp-content folder to your existing wp-content folder, overwriting existing files. Do NOT delete your existing wp-content folder. Do NOT delete any files or folders in your existing wp-content directory (except for the one being overwritten by new files).
  4. Upload all new loose files from the root directory of the new version to your existing WordPress root directory.

How to Update WordPress Plugins

Updating your WordPress plugins is a very similar process to updating WordPress core. Click into “Updates” in your WordPress dashboard, select the plugins you want to update, and click on “Update Plugins.”

Update WordPress plugins
Update WordPress plugins

Likewise, you can also update a plugin manually. Simply grab the latest version from the plugin developer or WordPress repository and upload it via FTP, overwriting the existing plugin within the /wp-content/plugins directory.

It’s also important to note that developers don’t always keep their plugins up to date. The team over at WP Loop did a great little analysis of just how many WordPress plugins in the repository aren’t up to date with the current WordPress core. According to their research nearly 50% of the plugins in the repository have not been updated in over 2 years.

This doesn’t mean the plugin won’t work with the current version of WordPress, but it’s recommended that you choose plugins that are actively updated. Out of date plugins are more likely to contain security vulnerabilities.

wordpress plugins not updated
img src: WP Loop

Use your best judgment when it comes to plugins. Look at the “Last Updated” date and how many ratings a plugin has. As seen in the example below, this one is out of date and has bad reviews so we would most likely recommend staying away from it. WordPress also has a warning at the top of most plugins that haven’t been updated in a while.

Old WordPress plugin with bad ratings
Old WordPress plugin with bad ratings

There are also a lot of resources out there to help you stay on top of the latest WordPress security updates and vulnerabilities. See some of them below:

WordPress security archive
WordPress security archive

5. Lock Down Your WordPress Admin

Sometimes the popular strategy of WordPress security by obscurity is appropriately effective for an average online business and WordPress site. If you make it harder for hackers to find certain backdoors then you are less likely to be attacked. Locking down your WordPress admin area and login is a good way to beef up your security. Two great ways to do this is first by changing your default wp-admin login URL and also limiting login attempts.

How to Change Your WordPress Login URL

By default your WordPress site’s login URL is domain.com/wp-admin. One of the problems with this is that all of the bots, hackers, and scripts out there also know this. By changing the URL you can make yourself less of a target and better protect yourself against brute force attacks. This is not a fix-all solution, it is simply one little trick that can definitely help protect you.

To change your WordPress login URL we recommend using the free WPS Hide login plugin or the premium Perfmatters plugin. Both of the plugins have a simple input field. Just remember to pick something unique that won’t already be on a list that a bot or script might attempt to scan.

Hide WordPress login URL with Perfmatters
Hide WordPress login URL with Perfmatters

How to Limit Login Attempts

While the above solution of changing your admin login URL can help decrease the majority of the bad login attempts, putting a limit in place can also be very effective. The free Limit Login Attempts Reloaded plugin is a great way to easily setup lockout durations, login attempts, and IP whitelists and blacklists.

Limit Login Attempts Reloaded plugin
Limit Login Attempts Reloaded

If you are looking for a more simple WordPress security solution, another great alternative is the free Login Lockdown plugin. Login LockDown records the IP address and timestamp of every failed login attempt. If more than a certain number of attempts are detected within a short period of time from the same IP range, then the login function is disabled for all requests from that range. And it is completely compatible with the WPS Hide login plugin we mentioned above.

login lockdown wordpress
Lockdown WordPress

How to Add Basic HTTP Authentication (htpasswd protection)

Another way to lock down your admin is to add HTTP authentication. This requires a username and password before being able to even access the WordPress login page. Note: This generally shouldn’t be used on eCommerce sites or membership sites. But it can be a very effective way to prevent bots from hitting your site.

.htpasswd authentication prompt
.htpasswd authentication prompt

Apache

If you are using a cPanel host, you can enable password protected directories from their control panel. To set it up manually, you will first need to create a .htpasswd file. You can use this handy generator tool. Then upload the file to a directory under your wp-admin folder, such as:

home/user/.htpasswds/public_html/wp-admin/htpasswd/

Then create a .htaccess file with the following code and upload it to your /wp-admin/ directory. Make sure you update the directory path and username.

AuthName "Admins Only"
AuthUserFile /home/yourdirectory/.htpasswds/public_html/wp-admin/htpasswd
AuthType basic
require user yourusername

The one caveat to doing it this way is that it will break AJAX (admin-ajax) on the front-end of your site. This is required by some third-party plugins. Therefore you will also need to add the following code to the above .htaccess file.

<Files admin-ajax.php>
Order allow,deny
Allow from all
Satisfy any
</Files>

Nginx

If you are running Nginx, you can also restrict access with HTTP basic authentication. Check out this tutorial.

If you host your WordPress site at Kinsta, you can use our easy password protection (htpasswd) tool in the MyKinsta dashboard. You can find it under the “Tools” section on your site. Simply click “Enable”, choose a username and password, and you’re good to go!

Enable .htpasswd protection
Enable .htpasswd protection

After it’s enabled your WordPress site will then require authentication to access it. You can change the credentials at any time or disable it when you no longer need it.

Lockdown a URL path

If you’re using a web application firewall (WAF) such as Cloudflare or Sucuri, they also have ways to lockdown a URL path. Essentially you can set up a rule so that only your IP address is able to access your WordPress admin login URL. Again, this generally shouldn’t be used on eCommerce sites or membership sites as they also rely on accessing your site’s back-end.

6. Take Advantage of Two-Factor Authentication

And of course, we can’t forget two-factor authentication! No matter how secure your password is there is always a risk of someone discovering it. Two-factor authentication involves a two-step process in which you need not only your password to login but a second method. It is generally a text (SMS), phone call, or time-based one-time password (TOTP). In most cases, this is 100% effective in preventing brute force attacks to your WordPress site. Why? Because it is almost impossible that the attacker will have both your password and your cellphone.

There are really two parts when it comes to two-factor authentication. The first is your account and or dashboard that you have with your web hosting provider. If someone gets access to this they could change your passwords, delete your websites, change DNS records, and all sorts of horrible things. We here at Kinsta partnered up with Authy and have two-factor authentication available for your MyKinsta dashboard.

The second part of two-factor authentication pertains to your actual WordPress installation. For this there are a couple plugins we recommend:

Many of these have their own Authenticator Apps you can install on your phone:

After installing and configuring one of the above plugins, you will typically have an additional field on your WordPress login page to enter your security code. Or, with the Duo plugin, you first log in with your credentials and are then required to choose an authentication method, such as Duo Push, call, or passcode.

This method can easily be combined with changing your default login URL, which we went over earlier. So not only is your WordPress login URL something only you know, but it now requires extra authentication to get in. 💪

WordPress two-factor authenticator page
WordPress two-factor authenticator page

So make sure to take advantage of two-factor authentication, it can be an easy way to beef up your WordPress security.

7. Use HTTPS for Encrypted Connections – SSL Certificate

One of the most overlooked ways to harden your WordPress security is to install an SSL certificate and run your site over HTTPS. HTTPS (Hyper Text Transfer Protocol Secure) is a mechanism that allows your browser or web application to securely connect with a website.  A big misconception is that if you aren’t accepting credit cards that you don’t need SSL.

Well, let us explain a few reasons why HTTPS is important beyond just eCommerce. Many hosts, including Kinsta, offer free SSL certificates with Let’s Encrypt.

HTTPS encrypted connections
HTTPS encrypted connections

1. Security

Of course, the biggest reason for HTTPS is the added security, and yes this does pertain strongly to eCommerce sites. However, how important is your login information? For those of you running multi-author WordPress websites, if you are running over HTTP, every time a person logs in, that information is being passed to the server in plain text. HTTPS is absolutely vital in maintaining a secure connection between a website and a browser. This way you can better prevent hackers and or a middle man from gaining access to your website.

So whether you have a blog, news site, agency, etc., they can all can benefit from HTTPS as this ensures nothing ever passes in plain text.

2. SEO

Google has officially said that HTTPS is a ranking factor. While it is only a small ranking factor, most of you would probably take any advantage you can get in SERPs to beat your competitors.

3. Trust and Credibility

According to a survey from GlobalSign, 28.9% of visitors look for the green address bar in their browser. And 77% of them are worried about their data being intercepted or misused online. By seeing that green padlock, customers will instantly have more peace of mind knowing that their data is more secure.

4. Referral Data

A lot of people don’t realize is that HTTPS to HTTP referral data is blocked in Google Analytics. So what happens to the data? Well, most of it is just lumped together with the “direct traffic” section. If someone is going from HTTP to HTTPS the referrer is still passed.

5. Chrome Warnings

As of July 24th, 2018, versions of Chrome 68 and higher started marking all non-HTTPS sites as “Not Secure.” Regardless of whether they collect data or not. This is why HTTPS is more important than ever!

This is especially important if your website gets a majority of its traffic from Chrome. You can look in Google Analytics under the Audience section in Browser & OS so see the percentage of traffic your WordPress site gets from Google Chrome. Google is making it a lot more clear to visitors that your WordPress website might not be running on a secured connection.

Chrome not secure website
Chrome not a secure website

6. Performance

Because of a protocol called HTTP/2, a lot of times, those running properly optimized sites over HTTPS can even see speed improvements. HTTP/2 requires HTTPS because of browser support. The improvement in performance is due to a variety of reasons such as HTTP/2 being able to support better multiplexing, parallelism, HPACK compression with Huffman encoding, the ALPN extension, and server push.

And with TLS 1.3, HTTPS connections are even faster. Kinsta supports TLS 1.3 on all of our servers and our Kinsta CDN.

Re-thinking HTTPS now? Check out our in-depth WordPress HTTPS migration guide to get you up and going and learn more in our TLS vs SSL comparision.

To enforce a secure, encrypted connection between you and the server when logging into and administering your site, add the following line to your wp-config.php file:

define('FORCE_SSL_ADMIN', true);

(Suggested reading: if you’re using legacy TLS versions, you might want to fix ERR_SSL_OBSOLETE_VERSION Notifications in Chrome).

8. Harden Your wp-config.php file

Your wp-config.php file is like the heart and soul of your WordPress installation. It is by far the most important file on your site when it comes to WordPress security. It contains your database login information and security keys which handle the encryption of information in cookies. Below are a couple things you can do to better protect this important file.

1. Move wp-config.php

By default, your wp-config.php file resides in the root directory of your WordPress installation (your /public HTML folder). But you can move this to a non-www accessible directory. Aaron Adams wrote up a great explanation of why this is beneficial.

To move your wp-config.php file simply copy everything out of it into a different file. Then in your wp-config.php file you can place the following snippet to simply include your other file. Note: the directory path might be different based on your web host and setup. Typically though it is simply one directory above.

<?php
include('/home/yourname/wp-config.php');

Note: this won’t work for Kinsta clients and will break functionality on our platform. This is because our open_basedir restrictions don’t allow execution of PHP above the ~/public directory for security reasons. The good news is we handle this for you! We do effectively the same thing by blocking access to wp-login.php within the ~/public directory. Our default Nginx config includes a rule that will return a 403 for any attempted access of wp-config.php.

2. Update WordPress Security Keys

WordPress security keys are a set of random variables that improve encryption of information stored in the user’s cookies. Since WordPress 2.7 there have been 4 different keys: AUTH_KEY, SECURE_AUTH_KEYLOGGED_IN_KEY, and NONCE_KEY.

When you install WordPress these are generated randomly for you. However, if you have gone through multiple migrations (check our curated list of the best WordPress migration plugins) or purchased a site from someone else, it can be good to create fresh WordPress keys.

WordPress actually has a free tool which you can use to generate random keys. You can update your current keys which are stored in your wp-config.php file.

WordPress security keys
WordPress security keys

Read more about WordPress security keys.

3. Change Permissions

Typically files in the root directory of a WordPress site will be set to 644, which means that files are readable and writeable by the owner of the file and readable by users in the group owner of that file and readable by everyone else. According to the WordPress documentation, the permissions on the wp-config.php file should be set to 440 or 400 to prevent other users on the server from reading it. You can easily change this with your FTP client.

wp-config.php permissions
wp-config.php permissions

On some hosting platforms, the permissions might need to be different because the user running the web server doesn’t have permission to write files. If you aren’t sure about this, check with your hosting provider.

9. Disable XML-RPC

In the past years XML-RPC has become an increasingly large target for brute force attacks. As Sucuri mentioned, one of the hidden features of XML-RPC is that you can use the system.multicall method to execute multiple methods inside a single request. That’s very useful as it allows an application to pass multiple commands within one HTTP request. But what also happens is that it is used for malicious intent.

There are a few WordPress plugins like Jetpack that rely on XML-RPC, but a majority of people out there won’t need this and it can be beneficial to simply disable access to it. Not sure if XML-RPC is currently running on your website? Danilo Ercoli, from the Automattic team, wrote a little tool called the XML-RPC Validator. You can run your WordPress site through that to see if it has XML-RPC enabled. If it isn’t, you will see a failure message such as shown in the image below on the Kinsta blog.

check wordpress xml-rpc
WordPress XML-RPC validator

To disable this completely you can install the free Disable XML-RPC-API plugin. Or you can disable it with the premium perfmatters plugin, which also contains web performance improvements.

If you are a customer here at Kinsta this is not needed because when an attack through XML-RPC is detected a little snippet of code is added into the NGINX config file to stop them in their tracks – producing a 403 error.

location ~* ^/xmlrpc.php$ {
return 403;
}

10. Hide Your WordPress Version

Hiding your WordPress version touches again on the subject of WordPress security by obscurity. The less other people know about your WordPress site configuration the better. If they see you are running an out of date WordPress installation, this could be a welcome sign to intruders. By default, the WordPress version shows up in the header of your site’s source code. Again, we recommend simply making sure your WordPress installation is always up to date so you don’t have to worry about this.

wordpress version source code
WordPress version in source code

You can use the following code to remove this. Simply add it to your WordPress theme’s functions.php file.

Important! Editing the source code of a WordPress theme could break your site if not done correctly. If you are not comfortable doing this, please check with a developer first.
function wp_version_remove_version() {
return '';
}
add_filter('the_generator', 'wp_version_remove_version');

You could also use a premium plugin like perfmatters (developed by a team member at Kinsta), which allows you to hide the WordPress version with one-click, along with other optimizations for your WordPress site.

Hide WordPress version with Perfmatters
Hide WordPress version with Perfmatters

Another place where the WordPress version shows up is in the default readme.html file (as shown below) that is included in every WordPress version. It is located in the root of your installation, domain.com/readme.html. You can safely delete this file via FTP.

wordpress version readme
WordPress version in readme file

If you’re running WordPress 5.0 or higher this is no longer applicable as the version number is no longer included in the file.

11. Add Latest HTTP Security Headers

Another step you can take to harden your WordPress security is to take advantage of HTTP security headers. These are usually configured at the web server level and tell the browser how to behave when handling your site’s content. There are a lot of different HTTP security headers, but below are typically the most important ones.

KeyCDN has a great in-depth post if you want to read more about HTTP security headers.

You can check which headers are currently running on your WordPress site by launching Chrome devtools and looking at the header on your site’s initial response. Below is an example on kinsta.com. You can see we are utilizing the strict-transport-security, x-content-type, and x-frame-options headers.

HTTP security headers
HTTP security headers

You can also scan your WordPress website with the free securityheaders.io tool by Scott Helme. This will show you which HTTP security headers you currently have on your site. If you aren’t sure how to implement them you can always ask your host if they can help.

http security headers scan
HTTP security headers scan

12. Use WordPress Security Plugins

And of course, we have to give some WordPress security plugins some mentions. There are a lot of great developers and companies out there which provide great solutions to help better protect your WordPress site. Here are a couple of them.

Kinsta has hardware firewalls, active and passive security, by-the-minute uptime checks and scores of other advanced features to prevent attackers from gaining access to your data. If, despite our best efforts, your site is compromised we’ll fix it for free.

Here are some typical features and uses of the plugins above:

  • Generate and force strong passwords when creating user profiles
  • Force passwords to expire and be reset on a regular basis
  • User action logging
  • Easy updates of WordPress security keys
  • Malware Scanning
  • Two-factor authentication
  • reCAPTCHAs
  • WordPress security firewalls
  • IP whitelisting
  • IP blacklisting
  • File changelogs
  • Monitor DNS changes
  • Block malicious networks
  • View WHOIS information on visitors

A very important feature that many security plugins include is a checksum utility. What this means is that they inspect your WordPress installation and look for modifications on the core files as provided by WordPress.org (via the API). Any changes or modifications to these files could indicate a hack. You can also use WP-CLI to run your own checksum.

Make sure to read our thorough guide on File Integrity Monitoring.

Another great plugin that deserves an honorable mention is the WP Security Audit Log plugin. This is awesome for those of you working on WordPress multisite or simply multi-author sites. It helps ensure user productivity and lets administrators see everything that is being changed; such as logins, password changes, theme changes, widget changes, new post creations, WordPress updates, etc.

It’s a complete WordPress activity log solution. As of writing this the WP Security Audit Log plugin has over 80,000+ active installs with a 4.7 out of 5-star rating. It is an excellent choice if you’re looking for a WordPress multisite compatible security solution.

wordpress security audit log
Security audit log viewer

It also has additional premium add-ons such as email notifications, user sessions management, search, and reports. Check out these additional WordPress security plugins that can help lock out the bad guys.

13. Harden Database Security

There are a couple ways to better the security on your WordPress database. The first is to use a clever database name. If your site is named volleyball tricks, by default your WordPress database is most likely named wp_volleyballtricks. By changing your database name to some more obscure it helps protect your site by making it more difficult for hackers to identify and access your database details.

A second recommendation is to use a different database table prefix. By default WordPress uses wp_. Changing this to something like 39xw_ can be much more secure. When you install WordPress it asks for a table prefix (as seen below). There are also ways to change the WordPress table prefix on existing installations. If you’re a Kinsta client, this isn’t needed. We’ve got site and databased locked down!

wordpress table prefix
WordPress table prefix – img src: jatinarora

14. Always Use Secure Connections

We can’t stress enough how important it is to use secure connections! Ensure that your WordPress host it taking precautions such as offering SFTP or SSH. SFTP or Secure File Transfer Protocol (also known as SSH file transfer protocol), is a network protocol used for file transfers. It is a more secure method vs standard FTP.

We only support SFTP connections at Kinsta to ensure your data remains safe and encrypted. Most WordPress hosts also typically use port 22 for SFTP. We take this a step further here at Kinsta and every site has a randomized port which can be found in your MyKinsta dashboard.

SFTP details in MyKinsta.
SFTP details in MyKinsta.

It’s also important to ensure that your home router is setup correctly. If someone hacks your home network they could gain access to all sorts of information, including possibly where your important information about your WordPress site(s) is stored. Here are some simple tips:

  • Don’t enable remote management (VPN). Typical users never use this feature and by keeping it off you can keep from exposing your network to the outside world.
  • Routers by default use IPs in the range such as 192.168.1.1. Use a different range, such as 10.9.8.7.
  • Enable the highest level of encryption on your Wifi.
  • IP white-list your Wifi so that only people with the password and certain IP can access it.
  • Keep the firmware on your router up to date.

And always be careful when logging into your WordPress site in public locations. Remember, Starbucks is not a secure network! Take precautions such as verifying the network SSID before you click connect. You can also use a 3rd party VPN service such as ExpressVPN to encrypt your internet traffic and hide your IP address from hackers.

15. Check File and Server Permissions

File permissions on both your installation and web server are crucial to beefing up your WordPress security. If permissions are too loose, someone could easily gain access to your site and wreak havoc. On the other hand, if your permissions are too strict this could break functionality on your site. So it is important to have the correct permissions set across the board.

File Permissions

  • Read permissions are assigned if the user has rights to read the file.
  • Write permissions are assigned if the user has rights to write or modify the file.
  • Execute permissions are assigned if the user has the rights to run the file and/or execute it as a script.

Directory Permissions

  • Read permissions are assigned if the user has the rights to access the contents of the identified folder/directory.
  • Write permissions are assigned if the user has the rights to add or delete files that are contained inside the folder/directory.
  • Execute permissions are assigned if the user has the rights to access the actual directory and perform functions and commands, including the ability to delete the data within the folder/directory.

You can use a free plugin like iThemes Security to scan the permissions on your WordPress site.

wordpress file permissions
WordPress file permissions scan

Here are some typical recommendations for permissions when it comes to file and folder permissions in WordPress. See the WordPress Codex article on changing file permissions for a more in-depth explanation.

  • All files should be 644 or 640. Exception: wp-config.php should be 440 or 400 to prevent other users on the server from reading it.
  • All directories should be 755 or 750.
  • No directories should ever be given 777, even upload directories.

16. Disable File Editing in WordPress Dashboard

A lot of WordPress sites have multiple users and administrators, which can make WordPress security more complicated. A very bad practice is to give authors or contributors administrator access, but unfortunately, it happens all the time. It is important to give users the correct roles and permissions so that they don’t break anything. Because of this, it can be beneficial to simply disable the “Appearance Editor” in WordPress.

Most of you have probably been there at one point or another. You go to quickly edit something in the Appearance Editor and suddenly you are left with a white screen of death. It is much better to edit the file locally and upload it via FTP. And of course, in best practice, you should be testing things like this on a development site first.

WordPress appearance editor
WordPress appearance editor

Also, if your WordPress site is hacked the very first thing they might do is try to edit a PHP file or theme via the Appearance Editor. This is a quick way for them to execute malicious code on your site. If they don’t have access to this from the dashboard, to begin with, it can help prevent attacks. Place the following code in your wp-config.php file to remove the ‘edit_themes’, ‘edit_plugins’ and ‘edit_files’ capabilities of all users.

define('DISALLOW_FILE_EDIT', true);

17. Prevent Hotlinking

The concept of hotlinking is very simple. You find an image on the Internet somewhere and use the URL of the image directly on your site. This image will be displayed on your website but it will be served from the original location. This is actually theft as it is using the hotlinked site’s bandwidth. This might not seem like a big deal, but it could generate a lot of extra costs.

The Oatmeal is a great example. The Huffington Post hotlinked a cartoon of his which consisted of multiple images and it racked up a whopping $1,000+ bill.

hotlinking
Hotlinking bill

Prevent Hotlinking in Apache

To prevent hotlinking in Apache simply add the following code to your .htaccess file.

RewriteEngine on
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http(s)?://(www\.)?yourdomain.com [NC]
RewriteRule \.(jpg|jpeg|png|gif)$ http://dropbox.com/hotlink-placeholder.jpg [NC,R,L]

The second row defines the allowed referrer – the site that is allowed to link to the image directly, this should be your actual website. If you want to allow multiple sites you can duplicate this row and replace the referrer. If you want to generate some more complex rules, take a look at this htaccess hotlink protection generator.

Prevent Hotlinking in NGINX

To prevent hotlinking in NGINX simply add the following code to your config file.

location ~ .(gif|png|jpe?g)$ {
valid_referers none blocked ~.google. ~.bing. ~.yahoo yourdomain.com *.yourdomain.com;
if ($invalid_referer) {
return 403;
}
}

Prevent Hotlinking on CDN

If you are serving your images from a CDN then the setup might be slightly different. Here are some resources with popular CDN providers.

18. Always Take Backups

Backups are the one thing everyone knows they need but don’t always take. Most of the recommendations above are security measures you can take to better protect yourself. But no matter how secure your site is, it will never be 100% safe. So you want backups in case the worst happens.

Most managed WordPress hosting providers now provide backups. Kinsta has five different types of backups, including automated backups that so that you can rest easy at night. You can even one-click restore your site.

Backups in MyKinsta.
Backups in MyKinsta.

If your host doesn’t have backups there are some popular WordPress services and plugins which you can use to automate the process.

WordPress Backup Services

WordPress site backup services usually have a low monthly fee and store your backups for you in the cloud.

WordPress Backup Plugins

WordPress backup plugins allow you to grab your backups via FTP or integrate with an external storage source such as Amazon S3, Google Cloud Storage, Google Drive, or Dropbox. We highly recommend going with an incremental solution so it uses fewer resources.

Note: We don’t allow non-incremental backup plugins on Kinsta servers due to performance issues. But this is because we handle all this for you at a server-level so it doesn’t slow down your WordPress site.

19. DDoS Protection

DDoS is a type of DOS attack where multiple systems are used to target a single system causing a Denial of Service (DoS) attack. DDoS attacks are nothing new – according to Britannica the first documented case dates back to early 2000. Unlike someone hacking your site, these types of attacks don’t normally harm your site but rather will simply take your site down for a few hours or days.

What can you do to protect yourself? One of the best recommendations is to use a reputable 3rd party security service like Cloudflare or Sucuri. If you are running a business it can make sense to invest in their premium plans. If you’re hosted on Kinsta, you don’t need to worry about setting up DDoS protection by yourself. All of our plans include a free Cloudflare integration with DDoS protection built-in.

DDoS protection from Cloudflare and Sucuri
DDoS protection from Cloudflare and Sucuri

Their advanced DDoS protection can be used to mitigate DDoS attacks of all forms and sizes including those that target the UDP and ICMP protocols, as well as SYN/ACK, DNS amplification and Layer 7 attacks. Other benefits include putting you behind a proxy which helps to hide your origin IP address, although it is not bulletproof.

Make sure to check out our case study on how to stop a DDoS attack. We had a client with a small e-commerce site running Easy Digital Downloads which got over 5 million requests to a single page within 7 days. The site typically only generated between 30-40 MB a day in bandwidth and a couple hundred visitors per day. But out of the blue, the site instantly went to between 15-19 GB of data transfer a day! That’s an increase of 4650%. And Google Analytics showed no additional traffic. So that is not good.

High bandwidth from DDoS attack
High bandwidth from DDoS attack

The client implemented Sucuri’s web application firewall on their site and all of the bandwidth and requests instantly dropped on the site (as seen below) and there hasn’t been a single issue since. So definitely a good investment and time saver if you are running into issues like these.

Added Sucuri web application firewall
Added Sucuri web application firewall

Summary

As you can see, there are numerous ways you can harden your WordPress security. Using clever passwords, keeping core and plugins up to date, and choosing a secure managed WordPress host are just a few that will keep your WordPress site up and running safely. For many of you, your WordPress site is your both your business and income, so it’s important to take some time and implement some of the security best practices mentioned above, sooner rather than later.

Have any important WordPress security tips that we missed? If so feel free to let us know below in the comments.

Brian Jackson

Brian has a huge passion for WordPress, has been using it for over a decade, and even develops a couple of premium plugins. Brian enjoys blogging, movies, and hiking. Connect with Brian on Twitter.