CVE-2025-7063: Widzialni Pad CMS RCE Vulnerability

CVE-2025-7063 Overview

CVE-2025-7063 is a critical unrestricted file upload vulnerability affecting PAD CMS, a content management system developed by Widzialni. The vulnerability exists due to a client-controlled permission check parameter in the file upload functionality, allowing unauthenticated remote attackers to upload files of any type and extension without restriction. These uploaded files can then be executed on the server, leading to Remote Code Execution (RCE).

This vulnerability impacts all three available templates: www, bip, and ww+bip. Critically, PAD CMS has reached End-of-Life status, and the vendor has confirmed they will not release security patches for this vulnerability.

Critical Impact

Unauthenticated attackers can achieve full remote code execution by uploading and executing malicious files, with no patches available due to the product's End-of-Life status.

Affected Products

• Widzialni PAD CMS (all versions)
• PAD CMS www template
• PAD CMS bip template
• PAD CMS ww+bip template

Discovery Timeline

• 2025-09-30 - CVE-2025-7063 published to NVD
• 2025-11-26 - Last updated in NVD database

Technical Details for CVE-2025-7063

Vulnerability Analysis

This vulnerability falls under CWE-434 (Unrestricted Upload of File with Dangerous Type). The core issue stems from the file upload functionality relying on a client-controlled parameter to determine whether permission checks should be enforced. Because this parameter can be manipulated by the attacker, the authentication and authorization controls become entirely ineffective.

The vulnerability is particularly severe because it requires no authentication and can be exploited remotely over the network. An attacker can craft HTTP requests that bypass the permission check entirely, allowing them to upload executable files such as PHP web shells, server-side scripts, or other malicious payloads directly to the web-accessible directory structure.

Root Cause

The root cause of this vulnerability is the improper trust placed in client-supplied data for security-critical decisions. The permission check parameter that should enforce upload restrictions is controllable by the client rather than being validated server-side. This represents a fundamental security design flaw where the server fails to enforce proper access controls independently of client input.

When the file upload handler receives a request, it checks a parameter value that the client can arbitrarily set, effectively allowing any remote user to bypass authentication requirements. Additionally, the absence of server-side file type validation means that even if authentication were properly enforced, dangerous file types could still be uploaded.

Attack Vector

The attack vector for CVE-2025-7063 is network-based, requiring no user interaction or authentication. An attacker can exploit this vulnerability by:

1. Identifying a vulnerable PAD CMS installation accessible over the network
2. Crafting an HTTP request to the file upload endpoint with manipulated permission check parameters
3. Uploading a malicious file (such as a PHP web shell) to the server
4. Accessing the uploaded file via its web-accessible path to trigger code execution

The attack complexity is low, as the exploitation requires only basic HTTP request manipulation capabilities. Once a malicious file is uploaded and executed, the attacker gains the ability to run arbitrary commands on the server with the privileges of the web server process.

For detailed technical analysis, refer to the CERT Poland Analysis of CVE-2025-7063.

Detection Methods for CVE-2025-7063

Indicators of Compromise

• Unexpected file uploads in web-accessible directories, particularly files with executable extensions (.php, .phtml, .jsp, etc.)
• Web server logs showing POST requests to file upload endpoints with unusual or manipulated parameters
• Newly created files in upload directories with timestamps that don't align with legitimate user activity
• Outbound network connections from the web server to unknown external IP addresses

Detection Strategies

• Monitor file system events for new file creation in PAD CMS upload directories
• Implement web application firewall (WAF) rules to detect and block requests attempting to upload executable file types
• Review HTTP access logs for POST requests to upload handlers with suspicious parameter patterns
• Deploy endpoint detection solutions capable of identifying web shell behaviors and anomalous script execution

Monitoring Recommendations

• Enable detailed logging for all file upload activities within PAD CMS
• Configure file integrity monitoring (FIM) on web server directories to alert on unauthorized file changes
• Implement network traffic analysis to detect command-and-control communications from compromised servers
• Set up alerts for web server processes spawning unexpected child processes

How to Mitigate CVE-2025-7063

Immediate Actions Required

• Immediately take PAD CMS installations offline if they are internet-facing
• Conduct a forensic review of existing upload directories for any previously uploaded malicious files
• If the system cannot be taken offline, implement network-level access controls to restrict access to trusted IP ranges only
• Begin planning migration to an actively supported content management system

Patch Information

No patches are available for this vulnerability. The vendor has confirmed that PAD CMS has reached End-of-Life status and no security updates will be released. Organizations using PAD CMS should prioritize migrating to an alternative, actively maintained content management system.

Workarounds

• Restrict network access to PAD CMS installations using firewall rules or VPN requirements
• Disable or remove the file upload functionality entirely if not required for business operations
• Implement server-side file type validation at the web server level (e.g., Apache/Nginx configuration) to reject executable file uploads
• Deploy a reverse proxy or WAF in front of the application to filter malicious upload attempts

# Example Apache configuration to block executable file uploads
<Directory "/var/www/html/pad_cms/uploads">
    # Disable script execution in upload directory
    php_admin_flag engine off
    
    # Block access to potentially dangerous file types
    <FilesMatch "\.(php|phtml|php3|php4|php5|pl|py|jsp|asp|aspx|cgi|sh)$">
        Require all denied
    </FilesMatch>
</Directory>