CVE-2025-39402: WPAMS Apartment Management RCE Vulnerability

CVE-2025-39402 Overview

CVE-2025-39402 is an Unrestricted Upload of File with Dangerous Type vulnerability (CWE-434) in the mojoomla WPAMS (WordPress Apartment Management System) plugin. This vulnerability allows attackers to upload a web shell to the web server, potentially leading to complete server compromise. The flaw exists because the plugin fails to properly validate file types during the upload process, enabling malicious actors to upload executable files disguised as legitimate content.

Critical Impact

Attackers can upload web shells to gain persistent remote access, execute arbitrary commands, and fully compromise the WordPress installation and underlying server infrastructure.

Affected Products

• WPAMS (WordPress Apartment Management System) plugin versions through 44.0 (17-08-2023)
• WordPress installations using the vulnerable apartment-management plugin
• Web servers hosting affected WordPress sites with the WPAMS plugin enabled

Discovery Timeline

• 2025-05-19 - CVE-2025-39402 published to NVD
• 2026-04-01 - Last updated in NVD database

Technical Details for CVE-2025-39402

Vulnerability Analysis

This vulnerability stems from improper file upload validation in the WPAMS apartment management plugin. The plugin accepts file uploads without adequately verifying the file type, extension, or content. This design flaw allows an attacker to bypass intended restrictions and upload files with dangerous extensions such as .php, .phtml, or other server-executable formats.

Once a malicious file is uploaded, the attacker can access it directly through the web server, triggering execution of the embedded code. Web shells uploaded through this vulnerability provide attackers with a persistent backdoor, enabling them to execute system commands, browse the file system, modify data, pivot to other systems on the network, and maintain long-term access even after initial compromise detection.

Root Cause

The root cause of CVE-2025-39402 is the absence of robust server-side file type validation in the WPAMS plugin's file upload functionality. The plugin relies on insufficient or client-side-only checks that can be easily bypassed. Proper validation should include MIME type verification, file extension whitelisting, file content inspection, and storing uploaded files outside the web root or with non-executable permissions.

Attack Vector

An attacker exploits this vulnerability by crafting a malicious HTTP request to the vulnerable file upload endpoint within the WPAMS plugin. The attack workflow typically involves:

1. Identifying a WordPress site running the vulnerable WPAMS plugin version
2. Locating the file upload functionality (typically within property management or image upload features)
3. Crafting a multipart form-data request with a PHP web shell disguised with a manipulated filename or MIME type
4. Uploading the malicious file to the server
5. Accessing the uploaded web shell via its URL to gain remote command execution

The vulnerability does not require authentication in certain configurations, making it particularly dangerous for publicly accessible WordPress installations. For detailed technical information, see the Patchstack Vulnerability Advisory.

Detection Methods for CVE-2025-39402

Indicators of Compromise

• Presence of unexpected PHP files in WordPress upload directories (e.g., wp-content/uploads/)
• Files with suspicious names or double extensions such as image.php.jpg or random character strings
• Unusual outbound network connections from the web server
• Web server access logs showing requests to newly created PHP files in upload directories
• Modification timestamps on files that don't align with legitimate administrative activity

Detection Strategies

• Monitor WordPress upload directories for newly created executable files (.php, .phtml, .phar)
• Implement file integrity monitoring (FIM) to detect unauthorized file additions
• Analyze web server access logs for POST requests to WPAMS plugin upload endpoints followed by GET requests to unusual file paths
• Deploy web application firewalls (WAF) with rules to detect web shell upload attempts
• Use endpoint detection and response (EDR) solutions to identify suspicious process execution by web server processes

Monitoring Recommendations

• Enable verbose logging for WordPress and the web server to capture file upload events
• Configure real-time alerting for new PHP files created in upload directories
• Implement automated scanning of upload directories using YARA rules for known web shell signatures
• Monitor for process spawning from web server processes (php-fpm, apache2, nginx) executing shell commands

How to Mitigate CVE-2025-39402

Immediate Actions Required

• Deactivate and remove the WPAMS (apartment-management) plugin immediately if running version 44.0 or earlier
• Audit WordPress upload directories for any suspicious or unauthorized files
• Review web server access logs for evidence of exploitation attempts
• Scan the server for web shells using security tools such as YARA, ClamAV, or commercial malware scanners
• Consider restoring from a known-good backup if compromise is suspected

Patch Information

As of the last CVE update, no official patch has been confirmed for versions through 44.0 (17-08-2023). Site administrators should check the Patchstack Vulnerability Advisory for the latest information on patches or updated versions. Until a patch is available, the plugin should be removed from production environments.

Workarounds

• Remove or deactivate the WPAMS plugin entirely until a patched version is released
• Implement strict file upload restrictions at the web server level using .htaccess or nginx configuration to prevent PHP execution in upload directories
• Deploy a Web Application Firewall (WAF) with rules to block file upload attempts containing executable content
• Restrict file upload functionality to authenticated administrative users only
• Configure upload directories with non-executable permissions at the operating system level

# Disable PHP execution in WordPress uploads directory (Apache)
# Add to wp-content/uploads/.htaccess
<Files *.php>
    deny from all
</Files>

# Alternative: Disable all script handlers in uploads
<FilesMatch "\.(php|phtml|php3|php4|php5|phar)$">
    Require all denied
</FilesMatch>