A hacker may be using a WordPress backdoor hack to tamper with your site without you even knowing it. Luckily, you can take action to resolve and prevent backdoor attacks on your site.
Cybersecurity is a major concern for any website today, regardless of niche or traffic level. Site operators and administrators need to make sure they are aware of the risks at hand. One of those risks is backdoors on WordPress sites.
This guide will cover everything you need to know about WordPress backdoor hacks, including the signs of an attack and ways to protect your site.
Table of Contents
What Is a WordPress Backdoor Hack?
A backdoor is an alternative, low-profile way into a system. A backdoor hack doesn’t use a brute-force approach. Instead, the hacker finds or creates a way for them to quietly access a system without anyone noticing – a “backdoor” into the “house.”
To put this into perspective, imagine if someone kicked down your front door. You would notice. On the other hand, you probably would not notice if someone simply used the unlocked door on the back porch. This is the idea behind backdoor WordPress hacks.
There are several ways a hacker could create or exploit a backdoor on your site. For instance, they might create or take advantage of a compromised plugin you have installed. Similarly, a hacker could use weak passwords to grant themselves administrator privileges on your site or create a backdoor.
Goals of Backdoor Hacks
You might be wondering why a hacker would carry out backdoor hacks on WordPress sites. It can be especially confusing given the fact that hackers will target sites of all audience sizes, not just popular sites. Experts point out that WordPress backdoor hacks are often part of large-scale automated attacks on many sites at once.
These attacks often aim to do things like redirect visitors on your site to malicious sites the hacker created. A hacker could also use the backdoor attack to add malicious links to your site, change or control your site, or use your site’s server resources for malicious purposes.
Even worse, backdoors could be used to infect your site, server, and possibly even devices with malware and ransomware – two of today’s most prominent cyber threats. Backdoor hacks can also be used to steal passwords and login credentials from your WordPress site, which could be used to hack into other accounts that share the same login info.
Signs of a WordPress Backdoor Hack
The frequency of ransomware attacks rose 518% in the first half of 2021 alone compared to previous years. This is a clear indication that cyber threats are on the rise and everyone could be at risk. Hackers could use ransomware to infect and hijack your WordPress site unless you agree to pay the attacker a certain amount of money.
Knowing the signs of a breached WordPress site is the first step to protecting yourself and your site from this kind of attack. There are a few common places to start looking for a backdoor attack. A backdoor is essentially part of your site’s infrastructure, so you are usually able to find the malicious code for the backdoor if you know where to look.
For example, hackers can hide their backdoor in the code for WordPress themes. These types of backdoor attacks exploit an intentional file in WordPress themes known as “functions.php.” The theme needs this file to run, but it can also be used to create a new administrator account on your site, often without you noticing.
You can check for a theme-based WordPress backdoor hack by going into your site’s theme code. Carefully look over the code’s “functions.php” file and search for anything that looks out of place – specifically, anything pertaining to “administrator,” new users, or admin access permissions.
Plugins can be extremely useful and helpful for operating and improving your WordPress site. Unfortunately, hackers can also take advantage of vulnerable plugins to create backdoor hacks.
Of course, there are plugins out there that are designed to be malicious. So, it helps to avoid plugins that are unpopular, from unknown developers, or lacking any reviews or support. If a plugin looks suspicious, it is usually best to play it safe and stay away from it.
However, plugin-based hacks can also simply be due to an attacker exploiting a bug in a legitimate WordPress plugin. So, make sure to check all your plugins, even if you think they are all trustworthy.
The best way to make sure your plugins are free from backdoors is to simply update them. One of the most common causes of plugin backdoor hacks is outdated plugins. So, make sure to keep your plugins updated. Additionally, clear out any plugins you aren’t using. Hackers may be able to hide a backdoor in these plugins more easily because they know you aren’t accessing them regularly.
Through compromised plugins, hackers will usually go into your site’s installation files to create their backdoor. So, you’ll have to go into your site’s code and check every line for legitimacy. Don’t ignore anything out of place. Backdoors can be disguised as “nonsense” lines of letters and numbers or even as seemingly harmless file types. Hackers may even use hex code to conceal their backdoor, so you may need to translate some disguised code.
How to Resolve and Prevent Backdoor Hacks
Finding a backdoor hidden on your WordPress site is not easy at first glance. Luckily, there are some tools that can help get rid of any backdoors on your site.
The best place to start is with checksums. These are copies of clean, verified code for your site, plugins, and themes. You can compare the checksum code to your site’s code to easily find anything that’s out of place.
It is possible to manually compare the checksum and the actual code, but there are also many automated programs available to do this for you. Before using a checksum verification program, just make sure to do your due diligence and research the program’s legitimacy.
Look for Known Backdoors
In addition to checksum files, it is also helpful to get a “blacklist” of known PHP and WordPress backdoors. You can use backdoors that others have already identified on their sites to quickly find any common backdoors on your WordPress site. Be careful not to download anything to your site while comparing the known backdoor code, though.
When you find any code that is out of place, make note of the suspicious code. Sometimes it will be obvious if it is a backdoor, such as PHP files that create new administrator accounts. Other times, you may need to reach out to WordPress support or plugin developers to confirm that the code is bad.
In either case, once you know you’ve found malicious code on your site, delete it and then update WordPress and all of your plugins. It’s also a good idea to change your login credentials.
Preventing Backdoor Attacks
One of the best ways to prevent backdoor attacks is to use strong login credentials for your site and your WordPress account. Use multi-factor authentication whenever possible. This login method is extremely difficult to hack since it requires verification from multiple sources, such as your login credentials plus a random code sent to your mobile phone.
Additionally, make sure you keep everything on your WordPress site updated. This is arguably the easiest way to prevent backdoor attacks. Check for WordPress updates regularly and do the same for all of your plugins and themes. If you are not actively using a theme or plugin, remove it from your site. It is also a good idea to regularly conduct scans of your site so you can identify malicious code quickly.
Keeping Your WordPress Site Secure
Backdoor hacks may sound scary, but they don’t have to be. You can stay ahead of hackers by keeping a close eye on your WordPress site and taking good care of it. WordPress backdoor hacks bet on users neglecting to update and clean up their sites. So, you can stop backdoor hacks in their tracks by updating all of your plugins and themes and regularly checking your site for anything out of place. With a little attention to detail, you can keep your site safe and secure!