8 Common WordPress Malware Types

WordPress powers over 40% of websites, making it a prime target for malware attacks. Malware can harm your site, steal sensitive data, and damage your reputation. Here’s a quick overview of the 8 most common types of malware affecting WordPress sites and how to protect against them:

1. Backdoor Attacks: Hidden access points bypassing security protocols.
2. Hidden SEO Spam: Injects spammy links to manipulate search rankings.
3. Pharmacy Spam Attacks: Promotes illegal pharmaceuticals through your site.
4. Forced Website Redirects: Redirects users to malicious or spammy sites.
5. Hidden Crypto Mining Code: Uses your site to mine cryptocurrency.
6. Compromised File Managers: Exploits vulnerabilities in file manager plugins.
7. Malicious JavaScript Code: Steals user data or alters site behavior.
8. Core File Changes: Modifies critical WordPress files for long-term control.

Quick Prevention Tips:

• Regularly update WordPress, plugins, and themes.
• Use strong passwords and enable two-factor authentication.
• Install a trusted security plugin with a firewall.
• Perform regular backups and malware scans.
• Monitor file changes and restrict file permissions.

Malware can lead to lost traffic, financial losses, and a damaged reputation. Staying proactive with security measures is key to protecting your site.

The Ultimate WordPress Security Guide To Prevent Hacking & Malware Attacks

1. Backdoor Attacks

Backdoor attacks create hidden access points that bypass standard security protocols, even after a breach has been addressed. These can take the form of small code snippets, files, compromised admin accounts, or cron jobs.

Shockingly, 30% of websites are hacked due to backdoors and related vulnerabilities. Once a backdoor is in place, attackers can sidestep normal authentication and inject harmful code into your site. This highlights the pressing need for strong security practices.

In June 2024, a backdoor found in five widely-used plugins impacted approximately 36,000 websites. The affected plugins were:

• Social Warfare
• BLAZE Retail Widget
• Wrapper Link Elementor
• Contact Form 7 Multi-Step Addon
• Simply Show Hooks

Common Warning Signs of Backdoor Attacks

Be on the lookout for these indicators:

How to Protect Your Site

Take these steps to safeguard against backdoor attacks:

• Use a Web Application Firewall (WAF) to block malicious traffic.
• Enable two-factor authentication for all admin accounts.
• Run regular scans with tools like MalCare or Sucuri.
• Monitor file directories for unexpected changes, especially in themes, plugins, and uploads.
• Keep all software updated, including WordPress, themes, and plugins.

If you suspect a backdoor attack, reach out to experts like WP Support Specialists (wpsupportspecialists.com) for professional help.

Backdoors can survive software updates and often hide more advanced threats behind decoys. Stay vigilant and proactive to minimize risks.

2. Hidden SEO Spam

Hidden SEO spam involves injecting unwanted links or content into a website to manipulate search engine rankings. Sucuri’s research highlights that 4.3% of WordPress sites scanned in 2021 were affected by this type of attack.

How SEO Spam Hurts Your Site

Hidden SEO spam can cause serious problems, including:

• Your site being deindexed or blacklisted by search engines
• A sudden drop in legitimate traffic
• Damage to your brand’s reputation
• Slower site performance
• Annoying redirects or pop-ups for visitors

Signs of SEO Spam on Your Site

Watch for these red flags:

• Unusual Content Changes: Pages or posts appear without your approval.
• Irrelevant Search Results: Strange or unrelated content shows up in search results.
• Traffic Issues: Analytics reveal odd spikes or drops in traffic.
• Changed Metadata: Page titles or meta descriptions are altered without your input.
• Fake User Accounts: A surge of spam accounts or irrelevant comments.

“Spam can decrease your website’s performance and harm its credibility, making it look unprofessional and untrustworthy. Worse still, search engines can blacklist your entire domain if it’s deemed unsafe for users, causing your pages to be deindexed and disappear from search results entirely.”
– David G Johnson, Product Owner, Solid WP

Steps to Recover from SEO Spam

If you suspect your site has been targeted, act quickly:

1. Scan and Clean: Use reliable security plugins to scan your site. Check your themes and plugins for any unauthorized changes.
2. Secure Access: Remove suspicious user accounts, update passwords, and ensure only trusted users have access to Google Search Console.
3. Fix Search Visibility: Clear your website cache, submit a clean sitemap to Google, and request re-indexing for your site.

How to Protect Your Site

Reduce the risk of SEO spam by taking these precautions:

• Install a trusted security plugin with firewall features.
• Keep your SSL certificate current.
• Regularly update your WordPress core, themes, and plugins.
• Enable two-factor authentication for admin accounts.
• Perform weekly security scans to catch problems early.

Using tools like Google Search Console to monitor your site’s performance can help you detect spam early. If managing these issues feels overwhelming, consider professional services like WP Support Specialists (https://wpsupportspecialists.com), which offer tailored WordPress security solutions. Up next, we’ll look at another common threat to WordPress sites.

3. Pharmacy Spam Attacks

Pharmacy spam attacks target WordPress sites to promote illegal pharmaceuticals. In 2022, SiteCheck data revealed that over 40% of SEO spam infections involved pharma spam injections.

How Pharmacy Spam Works

These attacks inject hidden pharmaceutical-related content into WordPress websites. The goal? To exploit your site’s SEO authority and sneak past Google’s restrictions on pharmaceutical ads. While regular visitors see your standard content, search engines index a version stuffed with pharma keywords and links. These changes are often subtle but leave behind telltale signs.

Warning Signs of Infection

Look out for these red flags:

• Pharma-related terms showing up in search results for your site
• A sudden drop in organic traffic
• Alerts from Google Search Console about security issues
• Redirects to online pharmacy websites
• Unauthorized changes to your sitemap

Impact on Your Website

“The malware takes over your website, piggybacking off your website resources and SEO, and often redirects your visitors to these shady sites. When Googlebot crawls your website, it will find the malware and blacklist your website. And finally, your web host will detect malware and suspend the site. All of these consequences will lead to your SEO rankings bottoming out, an end to organic traffic, and a hit to your site’s reputation and brand.”

The fallout can be devastating. Quick detection and recovery are crucial to minimizing the damage.

Detection and Recovery Steps

Here’s how to identify and remove pharmacy spam:

1. Search for “inurl:yoursite.com viagra or cialis” to check for unauthorized content.
2. Scan your site for malware using tools like Sucuri SiteCheck.
3. Examine core files (such as index.php, .htaccess, and wp-config.php) for suspicious changes.
4. Review your database tables – especially wp_options and wp_posts – for unusual entries.

Prevention Measures

To reduce the likelihood of future infections, take these precautions:

• Use security plugins with firewall features.
• Create and maintain daily backups of your site.
• Keep WordPress core, themes, and plugins up to date.
• Enforce strong password policies for all users.
• Regularly monitor your site’s search results for anomalies.
• Apply WordPress hardening techniques to tighten security.

Basic security plugins start at around $99 per year, but recovering from a pharmacy spam attack – including business losses and reputation damage – can cost far more. For professional help, WP Support Specialists (https://wpsupportspecialists.com) provides WordPress security and malware removal services.

4. Forced Website Redirects

In 2024, more than 60% of infected WordPress sites were affected by redirect malware.

How Redirect Malware Works

Redirect malware operates by injecting malicious code into key files like .htaccess, index.php, functions.php, core files, or JavaScript. It often uses tactics such as cookies or IP filtering to avoid detection. This malware can trigger redirects when users click anywhere on the site or interact with deceptive “ALLOW” buttons.

Common Redirect Patterns

One analysis highlighted a typical chain of redirects: “Some sites redirect to clicks.xxfdftrafficx[.]com, then to wwwx.xdsfdstraffic[.]com, then to red.goabcdforward[.]com, yellowlabel[.]com, or ticker[.]records[.]com before landing on one of the sites”. Recognizing patterns like this can help identify infections.

Warning Signs

Here are some red flags that might indicate your site is infected with redirect malware:

• Unexplained drops in traffic
• Increased bounce rates
• 404 errors when accessing wp-admin
• Alerts from Google Search Console
• Unexpected pop-ups
• User reports about automatic redirects

Impact on Your Website

Redirect malware can lead to a range of problems, including:

Protection Measures

Here’s how to protect your WordPress site from redirect malware:

• Keep everything updated: Regularly update WordPress core, themes, and plugins.
• Monitor your files: Check for unexpected changes in your website’s files.
• Use trusted security tools: Install security plugins with real-time monitoring.
• Strengthen your passwords: Enforce strong password policies for all accounts.
• Remove unused components: Delete inactive themes and plugins.
• Avoid pirated software: Never install nulled themes or plugins.

“WordPress site redirect hack is one of the most exploited attacks among WP hackers”.

For expert help with malware removal and securing your site, check out WP Support Specialists (https://wpsupportspecialists.com). They offer customized WordPress solutions tailored to your needs.

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5. Hidden Crypto Mining Code

Hidden crypto mining code, often referred to as cryptojacking, is a growing problem for WordPress sites. This type of malware sneaks in and uses your visitors’ CPU power to mine cryptocurrency – without their knowledge.

How Cryptojacking Works

Cryptojackers inject malicious code into a WordPress site. Once active, the script runs every time a page loads, draining CPU resources to mine cryptocurrency. According to Checkpoint research, a site with 1,000 active users could generate up to $2,398 per month for the attackers.

Warning Signs

If your WordPress site has been compromised by cryptojacking, you might notice:

Real-World Example

In August 2021, the Sysdig Security Research team discovered a large-scale cryptomining attack targeting WordPress sites. This attack, linked to the Sysrv-Hello Botnet, exploited sites with weak or default credentials. The attackers installed cryptominers and spread the malware across vulnerable systems. They even used newly compiled binaries that initially bypassed many malware detection tools.

“Botnet and Crypto miner attacks are on the rise, and they come in many different forms. The fact that crypto currency prices crashed early in the year is not making things better. After all, your infrastructure is still free money for the attackers.” – Stefano Chierici

Protection Measures

To protect your WordPress site from cryptojacking, take these steps:

• Monitor System Resources: Keep an eye on your site’s CPU usage trends for unusual activity.
• Use Security Tools: Install a web application firewall (WAF) for added protection.
• Scan Regularly: Run security plugins to check for malicious mining scripts.
• Strengthen Access Control: Use strong, unique passwords for all accounts.
• Update Everything: Regularly update WordPress core, themes, and plugins.

“At its core, CoinHive is malware that harnesses a computer’s processing power for cryptocurrency mining. It gains access to your visitors’ computers by infecting your site with malware.” – Shreya Nair

Although cryptomining malware makes up less than 4% of all malware detections, its impact on site performance and user experience can be severe. Routine security checks and proactive monitoring are essential to keep your WordPress site safe. For expert help, WP Support Specialists (https://wpsupportspecialists.com) offer professional WordPress security services.

6. Compromised File Managers

File manager plugins might make tasks easier, but they can also open doors to serious vulnerabilities, often exploited for unauthorized server access.

The WP File Manager Breach

In 2020, a major vulnerability in the WP File Manager plugin impacted over 700,000 WordPress sites. Attackers exploited this flaw to execute remote code, gaining full control of affected websites. Here’s what hackers can do:

This is just one example of how compromised file managers can lead to broader security issues, similar to other WordPress malware threats.

“If you care about your website’s security, you should never install a file manager plugin.” – Nora Kramer, Designer + Brand Strategist, Nora Kramer Designs

Signs Your File Manager Is Compromised

Watch for these red flags to detect a compromised file manager:

• New, unauthorized user accounts in your WordPress dashboard
• Strange files with random names appearing unexpectedly
• PHP or JavaScript files in the wp-content/uploads directory
• Unusual changes to timestamps on core WordPress files
• Redirects to unfamiliar or suspicious domains

Key Steps to Strengthen Security

1. Restrict File Permissions
   Apply these permissions to critical files and directories:
   • wp-config.php: 0600
   • Regular files: 0644
   • Directories: 0755
2. Protect Directories
   Block PHP execution, disable directory browsing, and limit access to sensitive files.
3. Enhance Access Control
   Use secure alternatives like SFTP, enable two-factor authentication, restrict admin access by IP whitelisting, and deploy a web application firewall (WAF).

“File manager plugins may seem convenient, but they introduce significant security risks that can lead to malware infections, data breaches, and complete site takeovers.” – Nora Kramer, Designer + Brand Strategist, Nora Kramer Designs

If your file manager is compromised, switch to safer tools like cPanel or SFTP immediately. Consider reaching out to WordPress support specialists for help. This highlights why securing file management tools is just as critical as defending against other WordPress malware threats.

7. Malicious JavaScript Code

WordPress sites often face threats from malicious JavaScript injections, which can secretly alter site behavior and compromise user data. This type of malware is particularly dangerous because it can steal sensitive information while operating undetected.

Recent JavaScript Attack Campaigns

In early 2023, over 51,000 WordPress websites, including hundreds from the Tranco top 1 million, were targeted in a large-scale JavaScript injection campaign. Attackers employed advanced techniques such as:

By understanding these techniques, you can better identify and address vulnerabilities.

Common Injection Points

Malicious JavaScript frequently targets essential system components, similar to how backdoors or compromised file managers work. Common injection sites include:

• Core theme files (e.g., header.php)
• jQuery and other JavaScript libraries
• Plugin JavaScript files
• Database entries in wp_options and wp_posts

These vulnerabilities have led to significant breaches.

“The websites all shared a common issue – malicious JavaScript had been injected within their website’s files and the database, including legitimate core WordPress files.”
– Krasimir Konov, Analyst at Sucuri

Real-World Impact

In May 2022, a specific attack infected more than 6,600 WordPress sites by embedding code into core JavaScript files. The targeted files included:

• ./wp-includes/js/jquery/jquery.min.js
• ./wp-includes/js/jquery/jquery-migrate.min.js

Sucuri reported that around 90% of their website cleanup requests involved WordPress sites affected by malicious redirects.

Detection Signs

Be on the lookout for these warning signs:

• Unexpected redirects
• Slower page loading times
• Browser security warnings
• Unusual pop-ups
• Modified timestamps on core JavaScript files

Essential Protection Steps

To safeguard your site, take the following steps:

1. Disable file editing in wp-config.php by adding:
   define('DISALLOW_FILE_EDIT', true);
2. Regularly scan for unauthorized script changes.
3. Keep WordPress, plugins, and themes updated to reduce risks.

“As new vulnerabilities in WordPress plugins are discovered, we anticipate that they will be caught up in the massive ongoing redirect campaign sending unsuspecting victims to fraudulent websites and tech support scams.”
– Sucuri

In January 2023, one malicious JavaScript campaign blocked around 240,000 sessions across 14,773 devices.

If you suspect malicious JavaScript activity on your site, consider reaching out to WP Support Specialists (https://wpsupportspecialists.com) for expert help.

8. Core File Changes

Core file changes are a serious concern for WordPress security. Attackers often modify key files to gain long-term control over compromised websites.

Common Attack Patterns

Hackers typically target critical files like:

One alarming case involved attackers modifying wp-includes/template-loader.php to redirect users to fake websites selling Windows keys, as reported by Sucuri.

Signs of Compromise

Be on the lookout for these red flags indicating core file tampering:

• Code snippets using base64_decode, eval, or gzinflate functions
• Changes in timestamps on WordPress system files
• Strange entries in wp_posts or wp_options database tables
• Slower website performance
• New admin accounts you didn’t create

“WordPress, being one of the most popular content management systems, is often a target for malicious activities. Unauthorised changes to your WordPress core files can compromise your site’s security and functionality.”
– Accreditly.io

Recognizing these signs early can help you act quickly to protect your site.

Key Protection Steps

To keep your core WordPress files safe:

• Use file integrity monitoring to detect changes.
• Set file permissions correctly to limit access.
• Enable a Web Application Firewall (WAF) for an added layer of security.
• Make regular backups and store them securely.
• Check server access logs for unusual activity.

“For every minute a website is redirecting to spam, the web property is losing credibility.”
– Bruno Zanelato, Sucuri’s Copywriter

How to Verify File Integrity

You can check for unauthorized changes using WP-CLI:

wp core verify-checksums

This compares your WordPress files with the official repository, flagging any unauthorized alterations.

If you find core file changes, act immediately to secure your site. For expert help with malware removal and tightening security, consider reaching out to WP Support Specialists (https://wpsupportspecialists.com).

Conclusion

WordPress malware poses a serious risk to the security of websites, impacting over 40% of all sites globally. As discussed earlier, these malware types – ranging from backdoor attacks to modifications of core files – demand a strong and proactive approach to security. Ignoring these threats can lead to traffic loss, financial damage, and a tarnished reputation.

Impact of WordPress Malware

Understanding the various forms of malware is key to safeguarding your site. A malware infection can have far-reaching consequences, including:

With 560,000 new malware threats emerging daily and ransomware attacks hitting four companies every minute, it’s clear that securing your site is not just important – it’s urgent.

Key Security Measures

To protect your WordPress site, consider implementing these essential steps:

• Use a trusted Web Application Firewall (WAF) to block harmful traffic.
• Set correct file permissions (directories: 755, files: 644).
• Enable two-factor authentication for all admin accounts.
• Regularly back up your site to an offsite location.
• Keep WordPress core, themes, and plugins updated to their latest versions.

“Making sure that your WordPress website is secure is crucial when it comes to the protection of sensitive information and the integrity of your brand. As cyber threats become more common, it is becoming a matter of great importance to ensure that your defenses are iron-clad.” – Stanley Walton, Junior SEO and Content Specialist

For those facing malware issues, professional services like WP Support Specialists (https://wpsupportspecialists.com) can offer expert help. Their team specializes in identifying and removing malicious code while bolstering your site’s defenses to prevent future attacks.

The best strategy is always prevention. With 4.7 million WordPress sites hacked annually, investing in strong security measures and regular maintenance isn’t optional – it’s essential for keeping your website secure and running smoothly.

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