CVE-2025-4923: Client Database Management System RCE Flaw

CVE-2025-4923 Overview

A critical unrestricted file upload vulnerability has been identified in SourceCodester Client Database Management System version 1.0. This vulnerability affects the file /user_delivery_update.php, where improper handling of the uploaded_file_cancelled parameter allows attackers to upload arbitrary files to the server without proper validation or restrictions.

Critical Impact

Remote attackers can exploit this vulnerability to upload malicious files, potentially leading to remote code execution, web shell deployment, or complete server compromise.

Affected Products

• SourceCodester Client Database Management System 1.0
• Lerouxyxchire Client Database Management System 1.0

Discovery Timeline

• 2025-05-19 - CVE-2025-4923 published to NVD
• 2025-05-28 - Last updated in NVD database

Technical Details for CVE-2025-4923

Vulnerability Analysis

This unrestricted file upload vulnerability (CWE-434) combined with improper access control (CWE-284) allows unauthenticated remote attackers to upload arbitrary files to the vulnerable web application. The vulnerability resides in the /user_delivery_update.php endpoint, which fails to properly validate or restrict file uploads through the uploaded_file_cancelled parameter.

The lack of file type validation, extension filtering, and content-type verification means attackers can upload executable files such as PHP web shells, which can then be accessed directly to execute arbitrary commands on the underlying server. This represents a complete breakdown of upload security controls, enabling full server compromise through a network-accessible attack surface requiring no user interaction.

Root Cause

The root cause of this vulnerability is the absence of proper input validation and file upload restrictions in the user_delivery_update.php file. The application fails to implement essential security controls including:

• File extension whitelisting or blacklisting
• MIME type validation
• File content inspection
• Upload directory restrictions preventing script execution
• Authentication requirements for the upload functionality

Attack Vector

The attack can be initiated remotely over the network without requiring authentication or user interaction. An attacker can craft a malicious HTTP POST request to /user_delivery_update.php with the uploaded_file_cancelled parameter containing a malicious file payload.

The exploitation flow involves uploading a PHP web shell or other malicious script through the vulnerable endpoint, then accessing the uploaded file directly through the web server to execute arbitrary commands. Since no authentication is required, any network-accessible instance of this application is vulnerable to exploitation.

For detailed technical analysis and proof-of-concept information, refer to the GitHub Issue Discussion and VulDB entry #309485.

Detection Methods for CVE-2025-4923

Indicators of Compromise

• Unusual file uploads in web-accessible directories, particularly PHP or other script files
• HTTP POST requests to /user_delivery_update.php containing file upload data with suspicious extensions
• New or modified files in upload directories with executable extensions (.php, .phtml, .php5)
• Web server logs showing access to recently uploaded script files followed by suspicious system activity

Detection Strategies

• Monitor HTTP traffic for POST requests to /user_delivery_update.php with file attachments containing script extensions
• Implement file integrity monitoring on web application directories to detect unauthorized file additions
• Configure web application firewall (WAF) rules to block file uploads with executable extensions
• Review web server access logs for patterns indicating web shell access attempts

Monitoring Recommendations

• Enable detailed logging for the /user_delivery_update.php endpoint and upload directories
• Deploy endpoint detection and response (EDR) solutions to monitor for web shell indicators and suspicious process execution
• Implement real-time alerting for new PHP files created in web-accessible directories
• Establish baseline monitoring for normal file upload patterns to detect anomalous activity

How to Mitigate CVE-2025-4923

Immediate Actions Required

• Remove or disable the /user_delivery_update.php file if it is not essential to operations
• Implement authentication requirements for all file upload functionality
• Configure the web server to deny script execution in upload directories
• Review and remove any suspicious files that may have been uploaded during the exposure window
• Consider taking the application offline until proper security controls can be implemented

Patch Information

As of the last update on 2025-05-28, no official vendor patch has been released for this vulnerability. Organizations using SourceCodester Client Database Management System 1.0 should implement the recommended workarounds and monitor the SourceCodester website for security updates.

For additional vulnerability details and tracking, consult the VulDB CTI entry.

Workarounds

• Implement strict file type validation by whitelisting only expected file extensions (e.g., .pdf, .jpg, .png)
• Add server-side MIME type verification to ensure uploaded file content matches expected types
• Store uploaded files outside the web root or in directories with script execution disabled
• Require authentication for all file upload endpoints
• Deploy a web application firewall (WAF) with rules to block malicious file uploads

# Apache .htaccess configuration to prevent script execution in upload directory
# Add this file to your uploads directory

# Disable PHP execution
<FilesMatch "\.ph(p[2-7]?|t|tml|ps)$">
    Require all denied
</FilesMatch>

# Alternative: Disable all handlers for this directory
RemoveHandler .php .phtml .php3 .php4 .php5 .php7 .phps

# Set handler to none for safety
<FilesMatch ".*">
    SetHandler none
    SetHandler default-handler
</FilesMatch>