What Is an SQL Injection Attack?

While some WordPress website owners believe worrying about a Structured Query Language (SQL) injection attack is a thing of the past, it’s still a real threat. If they aren’t careful, it could cause data or financial losses. How can they protect their site and their customers?

What is an SQL Injection Attack

An injection attack targets website or application vulnerabilities. It involves inputting malicious code or inputs to trick a system into interpreting unauthorized commands. The goal is to get it to perform unintended actions, such as revealing information or bypassing authentication.

In an SQL injection attack, an attacker enters malicious SQL code into a website’s input fields to execute commands for backend database manipulation. If they’re successful, they can view, modify, steal or delete information.

While WordPress has fortified itself against this attack type over the years, it is still susceptible. According to one 2024 study, 20.64% of reported vulnerabilities were related to SQL injection, making it the second-most commonly exploited. It’s considered a high-severity risk.

How an SQL Injection Attack Works

An attacker uses an input field — like a comment section, search bar or login page — to type SQL code and execute a malicious command. For example, they could enter the value “‘ admin” and a double dash in the username box to gain access without authorization.

A double dash is a comment indicator, meaning the rest of the query is ignored. Bad actors can use it to nullify the password requirement, enabling them to log in with the code entered in the username box.

This is one example of an SQL injection attack — many variations exist. The more creative an attacker is, the easier it’ll be to gain unauthorized access, exfiltrate sensitive data or modify database tables.

Types of SQL Injection Attacks

The three categories of SQL injection attacks — in-band, out-of-band and blind — break down into multiple subtypes. Each works differently and has a unique purpose.

Error-Based SQL Injection

In an error-based SQL injection attack, a bad actor uses code to intentionally generate an error. The message returned can reveal information about the database’s structure, helping them understand how to further exploit a website.

Boolean-Based SQL Injection

A boolean-based SQL injection attack involves sending an SQL query to the database to determine whether something is true or false. The response tells them whether it’s vulnerable to specific exploits.

Time-Based SQL Injection

In a time-based SQL injection attack, a bad actor sends an SQL query to a database. Depending on whether the response time is immediate or delayed, they can confirm the existence of various vulnerabilities.

Union-Based SQL Injection

An attacker using a union-based SQL injection attack leverages the UNION SQL operator to combine the results of multiple queries. This way, they can maliciously extract additional information from the database.

How These Attacks Impact WordPress Sites

Since WordPress uses the MySQL database management system, it’s susceptible to these kinds of injection attacks. Bad actors can steal proprietary documents like sales figures or product designs, expose administrative credentials, or alter mailing lists and customer transaction histories.

Database modification and deletion can be damaging — recovering from data loss may be virtually impossible, depending on what attackers tamper with. However, theft is more concerning. Websites that store customer information could face legal or regulatory action.

Indirect losses like reputation damage and customer loyalty loss can have long-term financial impacts. The average data breach cost $4.45 million in 2023 — up from $4.35 million in 2022. Therefore, businesses shouldn’t be shy about funneling funds and resources into defending against SQL injection attacks.

How to Defend Against SQL Injection Attacks

While WordPress has built-in defense mechanisms against injection attacks, it can’t guarantee total protection. Website owners should leverage their own security features to safeguard their website, data and customers.

Leverage Input Validation

Input validation filters user-submitted text to ensure it is safe and doesn’t contain malicious SQL code. Website owners can use it to block symbols, preventing attackers from executing unauthorized commands.

Change the Site’s Prefix

WordPress adds the prefix “wp_” to every database file by default, meaning tables are named “wp_users” or “wp_posts.” Attackers know this — and often exploit it during injection attacks. Website administrators should use wp-config.php to change it to something unique and difficult to guess. A random string of letters and numbers should work.

Use Plugins Selectively

While plugins and themes are useful, each has various associated security risks. Considering almost 50% of organizations experienced a cyberattack because of a third party in 2022, these potential vulnerabilities aren’t something to take lightly.

There were 279 SQL injection vulnerabilities in 2023, affecting numerous plugins and themes. Website owners should be selective, limiting their collection. They can further mitigate security risks by only using trusted third-party applications that update frequently.

Encrypt Sensitive Data

Encryption turns plaintext into unintelligible ciphertext, preventing bad actors from being able to use stolen data — it becomes worthless to them. While it may not deter injection attacks, it minimizes their financial and reputational impact. Website owners should strongly consider encrypting sensitive or customer information.

Stay Alert for SQL Injection Attack Attempts

Website owners should consider conducting audits, using monitoring tools or manually reviewing backend processes to determine whether bad actors have recently attempted injection attacks. While it isn’t as prevalent a threat as it was years ago, it still can cause significant damage.

Read more about the author .

Save 40%

On monthly and annual plans

Lifetime Deals

Only during BF sales!




We won't spam you. Unsubscribe any time.

Wait! Before you go!

Get 10% discount for any WP Security Ninja plan!


Subscribe to our newsletter for new releases, discounts and general WordPress Security news. Sprinkled with other interesting stuff :-)

WordPress Turns 20: Save 20% Now!



Code valid till June 26th 2023

10% OFF

Subscribe to our newsletter

* We do not spam or share your email

Discount on any Security Ninja plan

and get

Hi and welcome back :-)