A new malware campaign is targeting WordPress websites using a disguised malicious plugin that mimics a security tool. This plugin provides attackers with remote code execution, JavaScript injection, and persistent access, all while staying hidden. The malware was first discovered in January 2025 during a Wordfence site cleanup investigation. It modifies the ‘wp-cron.php’ file, which silently creates and reactivates a plugin called ‘WP-antymalwary-bot.php.’
Additional fake plugin names used include ‘addons.php,’ ‘wpconsole.php,’ ‘wp-performance-booster.php,’ and ‘scr.php.’ These malicious plugins reappear if deleted, thanks to the modified ‘wp-cron.php.’ Wordfence suspects the attackers gained initial access via compromised FTP credentials or hosting accounts. The exact infection chain is unknown due to missing server logs during investigation.
Once deployed, the plugin grants the attacker admin access via a feature called ‘emergency_login_all_admins.’ When a valid password is entered, the plugin fetches admin data from the database and logs the attacker in. It also sets up an unauthenticated REST API route to execute commands and inject code. This includes altering ‘header.php’ files and clearing plugin caches through POST requests.
A newer version injects base64-decoded JavaScript into a site’s <head> section to serve spam, ads, or redirect users. Researchers recommend checking modified ‘wp-cron.php’ and ‘header.php’ files for suspicious changes. Admins should also monitor logs for keywords like ‘emergency_login’ or ‘check_plugin.’ These indicators may reveal the presence of the malware and help guide further remediation efforts.
