How To Prevent SQL Injections?

Do SQL injection attacks worry you about your website? It’s possible that you are already aware of the attack’s effects if you are reading this. You will discover simple techniques for preventing SQL injections in this post.

A hacker may be able to take over and take control of your WordPress website through SQL injections. From there, they have the ability to reroute your traffic, steal sensitive information, insert spam links, alter search results by adding Japanese characters, and show advertisements for illicit goods. Your website and your company could suffer irreversible harm from this kind of attack.

Fortunately, by implementing the appropriate security precautions, SQL injections can be avoided. We address SQL injections in this guide, going over in-depth ways to prevent them and protect your WordPress website.

What Are SQL Injection Attacks?

Almost every WordPress website has sections where users can enter information. This could be a login form, a contact form, or a search bar for the website.

A visitor would fill out a contact form on your website with their information, including name, phone number, and email address.

contact form vulnerable for sql injection attack

This information is sent to the MySQL database on your website. This is where it is processed and kept.

Now, in order to guarantee that the data is checked and cleaned before it enters your database, these input fields need to be configured correctly. For instance, the contact form’s limitation to accepting only letters and numbers is a vulnerability. Ideally, it shouldn’t take symbols. Now, if your website receives any data via this form, a hacker may use it to their advantage and add a malicious SQL query, such as this one:

txtUserId = getRequestString(“UserId”);

txtSQL = “SELECT * FROM Users WHERE UserId = ” + txtUserId;

Hackers execute the script after it has been saved in your database to take over your website. After that, they can use SQL injections as an exploit, compromise your website, and do other nefarious things. They can begin phishing, directing customers to other websites, and other fraudulent activities.

Therefore, your website has a SQL injection vulnerability if it doesn’t sanitize the data from these input fields.

How Does An SQL Attack Work?

Hackers target websites that have gaps in their security or other vulnerabilities that make it simple for them to gain access. According to our observations, hackers are well aware that themes and plugins frequently have security flaws. Their constant search for websites with weak plugins and themes takes them all over the Internet.

We’ll utilize an example to clarify this. Assume that Mr. A is utilizing the “Contact Form” plugin to enable a form on his website’s Contact Page. Assume for the moment that this plugin’s 2.4 version contained a SQL injection vulnerability that the developers addressed and published an updated 2.4.1 version of.

The developers disclose the update’s purpose, thereby making the security flaw publicly known, at the time of release. This indicates that hackers are aware of a security vulnerability in the Contact Form plugin version 2.4.

Now that there isn’t enough time to run the update, Mr. X puts off installing it for a few weeks. This is the point of failure.

Once vulnerabilities are discovered, hackers use tools or vulnerability scanners to search the internet for websites that are using a specific plugin or theme version.

They will search for websites that use Contact Form 2.4 in this scenario. Once they locate the website, they will be aware of the precise online vulnerability, which will make hacking much simpler for them. Here, they’ll take advantage of the SQL injection vulnerability to access your website.

Types of SQL Injections

Hackers use two types of SQL injections:

1. Classic SQL injection – When you visit a website, your browser (like Chrome or Mozilla) sends a HTTP request to the website’s server to display the content. The web server fetches the content from the site’s database and sends it back to your browser. That’s how you are able to view the front end of a website.

Now, your website’s database contains all sorts of data including confidential data such as customer details, payment information, and usernames and passwords. Your database should be configured to release only the front-end data. All other confidential data should be safeguarded. But if these application security checks aren’t in place, hackers take advantage.

In a Classic SQL injection attack, hackers send malicious requests to your database retreiving data to their browser. But they use query strings to request for sensitive information such as login credentials of your website.If you haven’t protected this information, it will be sent to the hacker. In this way, they can get their hands on your login details and break into your site. Attackers can also use prepared statements as a way of executing the same or similar database statements repeatedly with high efficiency.

2. Blind SQL injection – In this, the hacker injects malicious scripts through input fields on your website. Once it gets stored in your database, they execute it to do all sorts of damage like changing the content of your site or even deleting your entire database.In this case, they can use the malicious scripts to gain administrator privileges as well.

Both scenarios can have a devastating impact on your website and your business. Luckily, you can prevent such attacks by taking the right security and input validation measures on your website.

Steps For Preventing SQL Injection Attacks

To prevent SQL injection attacks, you need to carry out a security assessment of your website. Here are two types of measures you can take to prevent SQL attacks – some are easy ones and some are complex and technical.

Easy Preventive Measures Against SQL Injection Attacks

1. Install a security plugin

Activating a website security plugin is the first step you need to take to protect your website. WordPress security plugins will monitor your site and prevent hackers from breaking in.

There are plenty of plugins to choose from, but based on what it has to offer, we choose MalCare. The plugin will automatically put up a web application firewall to defend your site against attacks. Hack attempts are identified and blocked.

Next, the plugin’s security scanner will scan your site thoroughly every day. If there’s any suspicious behavior or malicious activity on your site, you’ll be alerted immediately. You can take action and fix your site instantly with MalCare before Google gets a chance to blacklist your site or your hosting provider decides to suspend your site.

2. Update your website regularly

As we mentioned in our SQL injection example earlier, when developers find security flaws in their software, they fix it and release a new version that carries the security patch. You need to update to the new version in order to remove the flaw from your site.

wordpress core update

We suggest dedicating time once a week to update your WordPress core installation, themes, and plugins.

However, if you see that a security update is released, install the update immediately.

3. Only use trusted themes and plugins

WordPress is the most popular platform to build websites and that’s partly because of the plugins and themes that make it easy and affordable. But among the plethora of themes and plugins available, you need to choose carefully. Check the details of the plugin such as the number of active installs, the last updated date, and the version it’s been tested with.

plugin details

We recommend downloading them from the WordPress repository. For any other themes and plugins, you should do proper research to verify that they can be trusted. This is because some third-party themes and plugins can be maliciously crafted by hackers. It could also just be badly coded which opens it up to vulnerabilities.

4. Delete any pirated software on your site

Pirated or nulled themes and plugins are enticing. It gives you access to premium features for free. But unfortunately, these usually come with preloaded malware. Pirated software is an easy way for hackers to distribute their malware.

When you install it, the malware gets activated and infects your site. It’s best to stay away from such software.

5. Delete inactive themes and plugins

It’s common to install a plugin and completely forget about it for years. But this habit can expose your site to hackers. The more plugins and themes you have installed on your site, the more chances there are of vulnerabilities appearing and hackers taking advantage of them.

We suggest keeping only the plugins and themes you use. Delete the rest and make your site more secure. Also scan your existing themes and plugins regularly.

Technical Preventive Measures

These measures may require a bit more knowledge of the inner workings of WordPress. However, nowadays, there’s a plugin for everything. So you needn’t worry about the complexities involved in implementing these measures. We make it simple!

1. Change the default database table name

Your WordPress site is made up of files and a database. In your database, there are 11 tables by default. Each table houses various data and configurations. These tables are named with a prefix ‘wp_’. So the name of the tables can be wp_options, wp_users, wp_meta. You get the drift.

change default database table names for preventing sql injection

These names are the same across all WordPress sites and hackers know this. Hackers know which table stores what kind of data. When hackers insert malicious scripts on your website, they know where the script would be stored. Using a simple method, they can execute SQL commands to run malicious activities.

But if you change the name of the table, it can deter hackers from finding where the scripts are located. So when hacks try to inject SQL codes into your database tables, they won’t be able to figure out the table name.

You can do this by using a plugin like Change Table Prefix or Brozzme. Simply install one of them on your site and follow the steps.

You can also do this manually by editing your wp-config file. A word of caution – a slight misstep here could lead to database errors and site malfunctions. Take a backup before you proceed.

  • Go to your hosting account > cPanel > File Manager.
  • Here, access the public_html folder and right-click on wp-config file.
  • Select Edit and find the following code
    “$table_prefix = ‘wp_’;”
  • Replace it with –
    “$table_prefix = ‘test_’;”

You can choose any prefix of your choice. Here we’ve chosen ‘test_’ as the new database name. Once done, hackers won’t be able to locate their SQL commands.

2. Control field entries and data submissions

You can configure all input fields on your website to accept only certain types of data. For example, a name field should allow only alpha entries (letters) because there’s no reason why numeric characters should be entered here. Similarly, a contact number field should accept only numerals.

You can use the sanitize_text_field() function that sanitizes the user input. This input validation makes sure that entries that are not correct or simply dangerous can be blocked.

3. Harden your WordPress website

This is one of the most important steps you can take towards protecting your WordPress site against SQL injection attacks. What is website hardening?

A WordPress website offers you many functions to help you run the site. However, the majority of people don’t use many of these functions. WordPress.org recommends disabling or removing some of them if you don’t use them. This will reduce the chances of attacks as there are lesser elements for hackers to try!

Some WordPress hardening measures are:

  1. Disabling the file editor
  2. Disabling plugin or theme installations
  3. Implementing 2-factor authentication
  4. Limiting login attempts
  5. Changing WordPress security keys and salts
  6. Blocking PHP execution in unknown folders

To implement these measures, you can use a plugin like MalCare that lets you do this with just a few clicks.

malcare hardening

Or you can implement it manually by following our Guide on WordPress Hardening.

That brings us to the end of preventing SQL injection attacks. If you’ve implemented the measures we’ve discussed in this SQL injection cheat sheet, your site will be safe

Final Thoughts

Prevention really is better than cure. SQL injection attacks can cause unnecessary stress and severe financial burden.

Most of the measures we discussed today can be easily implemented with the use of plugins. So you needn’t be worried if you are not tech-savvy! You can still protect yourself!

Along with implementing these measures, we strongly suggest activating MalCare on your site. Its firewall will actively defend your website against attacks. It scans your site every day to check for hack attempts and malware on your site.

You can think of it as your website security guard that monitors your site and keeps the bad guys out. You can have peace of mind knowing your site is protected.

Agnes Berry