WordPress Backdoors: How to Scan for Hidden Threats and Protect Your Site


7-layers of Security for Your WordPress Site

Your website needs the most comprehensive security to protect it from the constant attacks it faces everyday.

scan wordpress backdoor

Backdoors are a common cause of hacked WordPress sites, and they can wreak havoc on your website’s security. Backdoors are essentially secret entrances that hackers create to allow them access to your site, even if you’ve fixed all other vulnerabilities. They can be incredibly hard to detect, but that is where a top WordPress security plugin comes into the picture.

Here are just a few of the issues that backdoors can cause on your site:

  • Unauthorized access to your site’s content and user data
  • Installation of malicious scripts and code
  • Spammy links and ads being added to your site without your knowledge
  • Redirection of your site’s traffic to malicious sites
  • Don’t underestimate the damage that malware can do to your website. It can seriously harm your online reputation, affect your search engine rankings, and cause a loss of revenue for your business.

But don’t worry, you don’t have to be a security expert to protect your site from backdoors. I’ll walk you through how to scan for hidden threats and protect your site from future attacks. You can trust that my advice is based on real-world experience dealing with hacked WordPress sites.

So, if you’re ready to take control of your site’s security, read on to find out how to identify and eliminate backdoors from your WordPress site. Together, we’ll make sure that your website is safe and secure.

TL;DR: Scan for backdoor infection on your WordPress site with MalCare. MalCare detects any malware hidden in site files and database in minutes, including multiple backdoors that other scanners miss. Once the backdoors have been found, you can remove them with MalCare’s one-click cleaner just as easily.

To protect your WordPress site from such attacks, it’s essential to regularly scan for backdoors using a WordPress security plugin. In this article, I’ll explain what backdoors are, why they’re dangerous, and how backdoor scanners can help you detect and remove them before they cause significant harm. I’ll also provide tips on choosing a backdoor scanner and how to scan for backdoors step-by-step.

What is a WordPress backdoor? 

A WordPress backdoor is a piece of code that is added to a site with the aim of allowing a hacker to gain unauthorised access without detection. Backdoors can be used to bypass login screens, create new admin accounts, steal sensitive data, or even take over the entire website.

💡 The only way to find backdoors effectively is to scan your site for malware.

Unlike other types of malware that are designed to cause obvious damage, a backdoor may not do anything on its own. Instead, it simply provides a way for the hacker to access the site whenever they want, without leaving any trace. Here some examples of common WordPress backdoors:

  • Hidden admin user
  • Mystery files not related to WordPress
  • Invalid code in core files
  • Manipulated plugins or themes

Backdoors are difficult to detect and remove. Even if all other malware has been removed, a backdoor can remain in place, allowing the hacker to continue to access the site and cause further damage. A blogger noticed that their website was loading slowly and occasionally redirecting to suspicious sites. After scanning their site with MalCare, they discovered multiple backdoors on the site. 

It’s important to note that backdoors are separate from vulnerabilities. Even if you resolve a vulnerability in a plugin or theme with an update, the backdoor will remain in place, allowing the hacker to continue to access the site. This is why regular scanning is crucial to identifying and removing backdoors.

In another case, a website administrator noticed unusual activity on their WordPress site, such as new user registrations and changes to the site’s content. After running a backdoor scanner, they discovered multiple backdoors that had been installed by hackers. Hackers often add many backdoors in case a few are discovered and removed, providing themselves with multiple entry points to the site. 

Find and remove backdoors in WordPress

To remove a WordPress backdoor hack, you need to first find it. To find a backdoor, you can use a variety of methods, including deep scanning, online scanning, and manual scanning.

Option 1. Using a deep scanner and cleaner

A deep scanner is a tool that scans your WordPress site for malware and vulnerabilities, including WordPress backdoors. It works by analysing your site’s code, and flagging any suspicious or malicious code.

MalCare is the most effective deep scanner for WordPress. With MalCare, you can scan your site for backdoors and other types of malware in just a few minutes. MalCare’s deep scanner is designed to detect even the most sophisticated backdoors, giving you peace of mind that your site is secure.

1. To install the MalCare plugin, log in to your WordPress dashboard and navigate to Plugins > Add New. Search for “MalCare” and install the plugin. Next, activate it and follow the on-screen instructions to connect your site to MalCare.

MalCare security plugin

2. After you’ve connected your site to MalCare, you can run a scan for backdoors and other types of malware. MalCare’s deep scanner will analyse your site’s code thoroughly.

Security overview in MalCare dashboard

3. Once the scan is complete, MalCare will provide you with a report to indicate if malware was detected. Upgrade your account to review the results and take action to remove any backdoors or other security threats.

Security report

The advantage of using a deep scanner like MalCare to find backdoors is that you can use MalCare’s removal feature to get rid of the backdoor in the next step. This enables you to remove backdoors from your site as fast as possible, because otherwise they can be exploited at any time.

Option 2. Using an online scanner

I strongly recommend using a thorough WordPress backdoor scanner like MalCare instead of relying solely on online scanners. I’ve seen too many cases where online scanners have missed critical backdoors that were deeply embedded within a website’s code.

Online scanners often only scrape the surface of your website, only checking for obvious signs of malware. They may not be able to detect more sophisticated attacks that are designed to evade detection.

Furthermore, they can give you a false sense of security if they give your website a clean bill of health. It’s important to remember that security is an ongoing process and that new threats can emerge at any time.

Online scanners may be a helpful starting point for identifying potential security issues. They are also a useful tool in a larger security strategy. However, unlike a more comprehensive WordPress backdoor scanner like MalCare, online scanners cannot remove the backdoor, even if it is able to find it.

Therefore, I highly encourage you to use MalCare instead to ensure that your site is fully protected. Your website’s security is too important to leave to chance, so take the necessary steps to safeguard it today.

Option 3. Manual scanning and removal

Manual scanning involves reviewing your site’s code line by line to identify any suspicious or malicious activity. This can be a time-consuming process and requires a good understanding of WordPress and coding.

If you’re comfortable with manual scanning, you can use tools like FileZilla or a text editor to review your site’s code. Look for any unfamiliar code or activity that could indicate the presence of a WordPress backdoor.

Here are a few examples of what to look for:

  • A PHP file that has been added to your site’s directory, allowing an attacker to execute arbitrary code and gain access to sensitive information.
  • A plugin or theme that has been modified to include malicious code that creates a WordPress backdoor on your site.
  • A database entry that grants an attacker administrative access to your site, allowing them to make changes and steal information without your knowledge.
  • A hidden script that allows an attacker to bypass your site’s login screen and gain access to the admin area without needing a password.

In many cases, backdoors are encrypted with a common function to avoid detection. So, in many cases, you may find obfuscated code—which is a series of unreadable characters—with functions such as: 

  • eval
  • base64_decode
  • gzinflate
  • preg_replace
  • str_rot13 

These functions are not malware themselves, but are used to hide malware from WordPress developers. 

These are just a few examples of what a backdoor might look like on your WordPress site. It’s important to remember that backdoors can take many different forms.

Why I do not recommend manual scanning or removal

I strongly recommend against manual scanning as a method to detect security issues on your website. While it may seem like a thorough approach, it can be time-consuming, error-prone, and ineffective. 

One of the main problems with manual scanning is that it’s difficult to know what you’re looking for. Security threats can be hidden in many different places on your website, and it’s not always obvious where to start. This can lead to wasted time and effort, and it can also increase the risk of overlooking important security issues.

Additionally, manual scanning can be prone to errors. Even the most experienced website owners can miss important security issues in the code. 

The stakes get even higher with manual malware removal. Unless you have a deep understanding of how plugins and themes are developed, it is difficult to distinguish between legitimate and malicious code. Many sites infected with backdoors have crashed beyond repair because a critical file has been misidentified as malware and been deleted. The safety course of action is always to use a dedicated backdoor scanner and removal plugin like MalCare.

What causes a backdoor infection?

There are a few reasons how a WordPress site gets infected with backdoors, or indeed other malware.

  1. Outdated plugins and themes: Updating WordPress and its plugins and themes is critical. If the updates are not installed, the site becomes an easy target for hackers to install backdoors.
  2. Poor password security: Passwords must be strong and unique to resist hacking attempts. Similarly, the website’s security settings need to be configured correctly to prevent unauthorized access.
  3. Nulled plugins or themes: Plugins and themes from unreliable sources can potentially carry malicious code or malware, unknowingly creating backdoor access to your site.
  4. Shared hosting infections: Shared hosting environments can pose a risk. If a single website on a shared cPanel, for instance, is infected with malware, it can potentially spread to other sites.

Additionally, WordPress allows various access points, including FTP, SSH, and WP-Admin. Each of these needs to be adequately protected. Any lapse in security may invite hackers to install a backdoor. Having a strong security plugin has help you stay on top of your site’s security, despite these many attack vectors.

Prevent future WordPress backdoor infections

Once you have removed any backdoors from your WordPress site, it is important to take steps to secure your website and prevent future breaches. Here are some recommended actions:

  1. Change all passwords: Change all passwords associated with your website, including the admin account, hosting account, FTP account, database credentials, and any other user accounts. Use strong and unique passwords for each account and enable two-factor authentication where possible.
  2. Update your WordPress core, plugins, and themes: Ensure that your website is running the latest versions of WordPress, plugins, and themes. This helps to patch any vulnerabilities that may have been exploited by the backdoor and prevent future attacks.
  3. Install a security plugin: Use a security plugin to scan your website for any remaining malware or suspicious code. This ensures that there are no other backdoors or security threats on your site. It will also safeguard your site against future attacks. 
  4. Monitor your website for suspicious activity: Keep an eye on your website for any suspicious activity, such as unauthorised login attempts or changes to your website’s files. Use a security plugin or monitoring service to alert you of any potential security threats.
  5. Backup your website regularly: Regularly backup your website’s files and database so that you can quickly restore your website in the event of a security breach or data loss.
  6. Remove any unused plugins that haven’t been updated for a while: Unused plugins can still pose a security risk, even if they are not actively being used on your website. Hackers can exploit vulnerabilities in outdated plugins to gain access to your site.

By taking these steps and sticking to a security checklist, you can help to prevent future security breaches and ensure the long-term security of your website.

Why do hackers install backdoors? 

A backdoor is a program or code that creates a secret entry point to a computer system or network that bypasses normal authentication and security mechanisms. In the context of a WordPress site, a backdoor is typically inserted into the site’s codebase, often through a vulnerable plugin, theme, or the WordPress core itself. Backdoors can be inserted by exploiting a vulnerability in the website’s security, such as a weak password, outdated software, or unsecured hosting environment.

Once a WordPress backdoor is installed, it can be used to execute arbitrary code, access sensitive data, and even take control of the entire website. Backdoors can be difficult to detect because they are designed to remain hidden and avoid detection. For example, backdoors may use obfuscation or encryption to make it harder for security tools to detect them.

Attackers can use backdoors for a variety of purposes, such as stealing user data, injecting malware or spam links, and using the website to launch further attacks on other websites or systems. Backdoors can also be used to maintain access to a compromised system, even if the original vulnerability that was used to gain access is patched.

Final takeaways

WordPress backdoor scanners are important tools for detecting and preventing backdoor attacks on your WordPress website. By regularly scanning your website for backdoors, you can identify and remove any malicious code that could compromise your website’s security. Remember to keep your website’s software and plugins up-to-date, use strong passwords, and limit access to sensitive information to further enhance your website’s security. Stay vigilant and take proactive measures to protect your website from potential threats.


What is a WordPress backdoor? 

A backdoor in WordPress is a malicious program or code that is inserted into a website to bypass normal authentication or security measures and allow unauthorised access or control.

Can backdoors be detected? 

Backdoors can be difficult to detect because they are designed to remain hidden and avoid detection. However, website owners can use security tools to scan their website for vulnerabilities and malware and monitor their website for suspicious activity to detect any backdoors that may have been installed.

What is a WordPress backdoor hack example? 

A backdoor example is the CryptoPHP backdoor, which was discovered in 2014 and was embedded in pirated versions of popular WordPress themes and plugins. The backdoor allowed attackers to gain control of the infected websites and use them to launch further attacks.

What is the purpose of a backdoor? 

The purpose of a backdoor is to provide unauthorised access or control to a computer system or network. Attackers can use backdoors to steal sensitive data, inject malware or spam links, or use the infected system to launch further attacks on other systems. Backdoors can also be used to maintain access to a compromised system, even if the original vulnerability that was used to gain access is patched.

Where is the backdoor in my WordPress site? 

A backdoor can be anywhere on a WordPress site: the core files and folders, plugin files and folders, theme files and folders, and even in the database. Typically, they are hidden from view, and made to look like legitimate files.

How to scan for WordPress backdoor code?

The best way to scan for WordPress backdoor code is to install MalCare on your site, and set it up for scanning. MalCare will alert you of any malware that is found on your site. 

How to tell if WordPress plugin has a backdoor?

Generally speaking, good plugins from reputable publishers will not have backdoors. This is usually a problem with nulled premium plugins from scammy sites. If you suspect a plugin you have installed has a backdoor, use MalCare to scan it for malware. 

How to find a backdoor in a hacked WordPress site and fix it?

You can find a backdoor in a WordPress site by using MalCare. MalCare scans every file and folder on your site, and the database for good measure. It can ferret out the smallest, most well-hidden bit of malware.


You may also like

Website logs
What are the Different Types of Website Logs?

Imagine driving a car without knowing your speed, engine temperature, or fuel levels. Sounds terrifying, right? Well, managing a website without understanding website logs is a bit like that. You…

What is Cross-Site Scripting (XSS) and How to Prevent It?

Websites can sometimes act strangely, showing unexpected pop-ups or exposing personal information. This isn’t just a glitch—it’s often due to a sneaky trick called Cross-Site Scripting (XSS). You might be…

How can we help you?

If you’re worried that your website has been hacked, MalCare can help you quickly fix the issue and secure your site to prevent future hacks.

My site is hacked – Help me clean it

Clean your site with MalCare’s AntiVirus solution within minutes. It will remove all malware from your complete site. Guaranteed.

Secure my WordPress Site from hackers

MalCare’s 7-Layer Security Offers Complete Protection for Your Website. 300,000+ Websites Trust MalCare for Total Defence from Attacks.