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Did you know that your WordPress site could be a target for hackers right now? Thats right! Today, WordPress powers over 43% of all websites on the internet. That kind of public news makes WordPress sites a big target for hackers.One of the most harmful ways they attack is through an SQL injection. A SQL injection may break your website, steal data, and destroy your content. More than that, they can lock you out of your website! Sounds scary, right? But dont worry, you can protect your site. That is what this article is about.What Is SQL?SQL stands for Structured Query Language. It is a way to talk to databases, which store and organize a lot of data, such as user details, posts, or comments on a website. SQL helps us ask the database for information or give it new data to store.When writing an SQL query, you ask the database a question or give it a task. For example, if you want to see all users on your site, an SQL query can retrieve that list.SQL is powerful and vital since all WordPress sites use databases to store content.What Is An SQL Injection Attack?WordPress SQL injection attacks try to gain access to your sites database. An SQL injection (SQLi) lets hackers exploit a vulnerable SQL query to run a query they made. The attack occurs when a hacker tricks a database into running harmful SQL commands.Hackers can send these commands via input fields on your site, such as those in login forms or search bars. If the website does not check input carefully, a command can grant access to the database. Imagine a hacker typing an SQL command instead of typing a username. It may fool the database and show private data such as passwords and emails. The attacker could use it to change or delete database data.Your database holds all your user-generated data and content. It stores pages, posts, links, comments, and users. For the bad guys, it is a goldmine of valuable data.SQL injections are dangerous as they let hackers steal data or take control of a website. A WordPress firewall prevents SQL injection attacks. Those attacks can compromise and hack sites very fast.SQL Injections: Three Main TypesThere are three main kinds of SQL injection attacks. Every type works in various ways, but they all try to fool the database. Were going to look at every single type.In-Band SQLiThis is perhaps the most common type of attack. A hacker sends the command and gets the results using the same communication method. It is to make a request and get the answer right away.There are two types of In-band SQLi injection attacks:Error-based SQLi,Union-based SQLi.With error-based SQLi, the hacker causes the database to give an error message. This message may reveal crucial data, such as database structure and settings.What about union-based SQLi attacks? The hacker uses the SQL UNION statement to combine their request with a standard query. It can give them access to other data stored in the database.Inferential SQLiWith inferential SQLi, the hacker will not see the results at once. Instead, they ask for database queries that give yes and no answers. Hackers can reveal the database structure or data by how the site responds.They do that in two common ways:Boolean-based SQLi,Time-based SQLi.Through Boolean-based SQLi, the hacker sends queries that can only be true or false. For example, is this user ID more than 100? This allows hackers to gather more data about the site based on how it reacts.In time-based SQLi, the hacker asks a query that makes the database take longer to reply if the answer is yes. They can figure out what they need to know due to the delay.Out-of-band SQLiOut-of-band SQLi is a less common but equally dangerous type of attack. Hackers use various ways to get results. Usually, they connect the database to a server they control.The hacker does not see the results all at once. However, they can get the data sent somewhere else via email or a network connection. This method applies when the site blocks ordinary SQL injection methods.Why Preventing SQL Injection Is CrucialSQL injections are a giant risk for websites. They can lead to various harms stolen data, website damage, legal issues, loss of trust, and more.Hackers can steal data like usernames, passwords, and emails. They may cause damage by deleting and changing your data. Besides, it messes up your site structure, making it unusable.Is your user data stolen? You might face legal troubles if your site treats sensitive data. People may lose trust in you if they see that your site gets hacked. As a result, the reputation of your site can suffer.Thus, it is so vital to prevent SQL injections before they occur.11 Ways To Prevent WordPress SQL Injection AttacksOK, so we know what SQL is and that WordPress relies on it. We also know that attackers take advantage of SQL vulnerabilities. Ive collected 11 tips for keeping your WordPress site free of SQL injections. The tips limit your vulnerability and secure your site from SQL injection attacks.1. Validate User InputSQL injection attacks usually occur via forms or input fields on your site. It could be inside a login form, a search box, a contact form, or a comment section. Does a hacker enter bad SQL commands into one of these fields? They may fool your site, giving them access to your database by running those commands.Hence, always sanitize and validate all input data on your site. Users should not be able to submit data if it does not follow a specific format. The easiest way to avoid this is to use a plugin like Formidable Forms, an advanced builder for adding forms. That said, WordPress has many built-in functions to sanitize and validate input on your own. It includes sanitize_text_field(), sanitize_email(), and sanitize_url().The validation cleans up user inputs before they get sent to your database. These functions strip out unwanted characters and ensure the data is safe to store.2. Avoid Dynamic SQLDynamic SQL allows you to create SQL statements on the fly at runtime. How does dynamic SQL work compared to static SQL? You can create flexible and general SQL queries adjusted to various conditions. As a result, dynamic SQL is typically slower than static SQL, as it demands runtime parsing.Dynamic SQL can be more vulnerable to SQL injection attacks. It occurs when the bad guy alters a query by injecting evil SQL code. The database may respond and run this harmful code. As a result, the attacker can access data, corrupt it, or even hack your entire database.How do you keep your WordPress site safe? Use prepared statements, stored procedures or parameterized queries.3. Regularly Update WordPress Themes And PluginsKeeping WordPress and all plugins updated is the first step in keeping your site safe. Hackers often look for old software versions with known security issues.There are regular security updates for WordPress, themes, and plugins. They fix security issues. You leave your site open to attacks as you ignore these updates.To stay safe, set up automatic updates for minor WordPress versions. Check for theme and plugin updates often. Only use trusted plugins from the official WordPress source or well-known developers.By updating often, you close many ways hackers could attack.4. Add A WordPress FirewallA firewall is one of the best ways to keep your WordPress website safe. It is a shield for your WordPress site and a security guard that checks all incoming traffic. The firewall decides who can enter your site and who gets blocked.There are five main types of WordPress firewalls:Plugin-based firewalls,Web application firewalls,Cloud-based firewalls,DNS-level firewalls,Application-level firewalls.Plugin-based firewalls you install on your WordPress site. They work from within your website to block the bad traffic. Web application firewalls filter, check and block the traffic to and from a web service. They detect and defend against risky security flaws that are most common in web traffic. Cloud-based firewalls work from outside your site. They block the bad traffic before it even reaches your site. DNS-level firewalls send your site traffic via their cloud proxy servers, only letting them direct real traffic to your web server. Finally, application-level firewalls check the traffic as it reaches your server. That means before loading most of the WordPress scripts.Stable security plugins like Sucuri and Wordfence can also act as firewalls.5. Hide Your WordPress VersionOlder WordPress versions display the WordPress version in the admin footer. Its not always a bad thing to show your version of WordPress. But revealing it does provide virtual ammo to hackers. They want to exploit vulnerabilities in outdated WordPress versions.Are you using an older WordPress version? You can still hide your WordPress version:With a security plugin such as Sucuri or Wordfence to clear the version number orBy adding a little bit of code to your functions.php file.function hide_wordpress_version() { return '';}add_filter('the_generator', 'hide_wordpress_version');This code stops your WordPress version number from showing in the themes header.php file and RSS feeds. It adds a small but helpful layer of security. Thus, it becomes more difficult for hackers to detect.6. Make Custom Database Error NoticesBad guys can see how your database is set up via error notices. Ensure creating a custom database error notice that users see to stop it. Hackers will find it harder to detect weak spots in your site when you hide error details. The site will stay much safer when you show less data on the front end.To do that, copy and paste the code into a new db-error.php file. Jeff Starr has a classic article on the topic from 2009 with an example:<?php // Custom WordPress Database Error Page header('HTTP/1.1 503 Service Temporarily Unavailable'); header('Status: 503 Service Temporarily Unavailable'); header('Retry-After: 600'); // 1 hour = 3600 seconds// If you want to send an email to yourself upon an error// mail("your@email.com", "Database Error", "There is a problem with the database!", "From: Db Error Watching");?><!DOCTYPE HTML><html> <head> <title>Database Error</title> <style> body { padding: 50px; background: #04A9EA; color: #fff; font-size: 30px; } .box { display: flex; align-items: center; justify-content: center; } </style></head> <body> <div class="box"> <h1>Something went wrong</h1> </div> </body></html>Now save the file in the root of your /wp-content/ folder for it to take effect.7. Set Access And Permission Limits For User RolesAssign only the permissions that each role demands to do its tasks. For example, Editors may not need access to the WordPress database or plugin settings. Improve site security by giving only the admin role full dashboard access. Limiting access to features for fewer roles reduces the odds of an SQL injection attack.8. Enable Two-factor AuthenticationA great way to protect your WordPress site is to apply two-factor authentication (2FA). Why? Since it adds an extra layer of security to your login page. Even if a hacker cracks your password, they still wont be able to log in without getting access to the 2FA code.Setting up 2FA on WordPress goes like this:Install a two-factor authentication plugin.Google Authenticator by miniOrange, Two-Factor, and WP 2FA by Melapress are good options.Pick your authentication method.The plugins often have three choices: SMS codes, authentication apps, or security keys.Link your account.Are you using Google Authenticator? Start and scan the QR code inside the plugin settings to connect it. If you use SMS, enter your phone number and get codes via text.Test it.Log out of WordPress and try to log in again. First, enter your username and password as always. Second, you complete the 2FA step and type in the code you receive via SMS or email.Enable backup codes (optional).Some plugins let you generate backup codes. Save these in a safe spot in case you lose access to your phone or email.9. Delete All Unneeded Database FunctionsAssure erasing tables you no longer use and delete junk or unapproved comments. Your database will be more resistant to hackers who try to exploit sensitive data.10. Monitor Your Site For Unusual ActivityWatch for unusual activity on your site. You can check for actions like many failed login attempts or strange traffic spikes. Security plugins such as Wordfence or Sucuri alert you when something seems odd. That helps to catch issues before they get worse.11. Backup Your Site RegularlyRunning regular backups is crucial. With a backup, you can quickly restore your site to its original state if it gets hacked. You want to do this anytime you execute a significant update on your site. Also, it regards updating your theme and plugins.Begin to create a plan for your backups so it suits your needs. For example, if you publish new content every day, then it may be a good idea to back up your database and files daily.Many security plugins offer automated backups. Of course, you can also use backup plugins like UpdraftPlus or Solid Security. You should store backup copies in various locations, such as Dropbox and Google Drive. It will give you peace of mind.How To Remove SQL Injection From Your SiteLets say you are already under attack and are dealing with an active SQL injection on your site. Its not like any of the preventative measures weve covered will help all that much. Heres what you can do to fight back and defend your site:Check your database for changes. Look for strange entries in user accounts, content, or plugin settings.Erase evil code. Scan your site with a security plugin like Wordfence or Sucuri to find and erase harmful code.Restore a clean backup. Is the damage vast? Restoring your site from an existing backup could be the best option.Change all passwords. Alter your passwords for the WordPress admin, the database, and the hosting account.Harden your site security. After cleaning your site, take the 11 steps we covered earlier to prevent future attacks.ConclusionHackers love weak sites. They look for easy ways to break in, steal data, and cause harm. One of the tricks they often use is SQL injection. If they find a way in, they can steal private data, alter your content, or even take over your site. Thats bad news both for you and your visitors.But here is the good news: You can stop them! It is possible to block these attacks before they happen by taking the correct steps. And you dont need to be a tech freak.Many people ignore website security until its too late. They think, Why would a hacker target my site? But hackers dont attack only big sites. They attack any site with weak security. So, even small blogs and new websites are in danger. Once a hacker gets in, this person can cause you lots of damage. Fixing a hacked site takes time, effort, and money. But stopping an attack before it happens? Thats much easier.Hackers dont sit and wait, so why should you? Thousands of sites get attacked daily, so dont let yours be the next one. Update your site, add a firewall, enable 2FA, and check your security settings. These small steps can help prevent giant issues in the future.Your site needs protection against the bad guys. You have worked hard to build it. Never neglect to update and protect it. After that, your site will be safer and sounder.