CVE-2024-0412: Csdeshang Dsshop Auth Bypass Vulnerability

CVE-2024-0412 Overview

A vulnerability has been identified in DeShang DSShop versions up to and including 3.1.0 that allows improper access controls in the HTTP GET Request Handler. The vulnerability exists in the public/install.php file and can be exploited remotely by unauthenticated attackers. The exploit details have been disclosed publicly, increasing the risk of exploitation in the wild.

Critical Impact

This vulnerability allows remote attackers to bypass access controls in the installation component, potentially leading to unauthorized system configuration changes, data compromise, or complete system takeover.

Affected Products

• DeShang DSShop version 3.0
• DeShang DSShop version 3.1.0
• All DeShang DSShop versions up to 3.1.0

Discovery Timeline

• 2024-01-11 - CVE-2024-0412 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2024-0412

Vulnerability Analysis

This vulnerability represents a Broken Access Control flaw (CWE-284) in the DeShang DSShop e-commerce platform. The issue resides in the public/install.php file, which handles HTTP GET requests for the application's installation process. Due to improper access control implementation, the installation script remains accessible after initial deployment, allowing remote attackers to manipulate the application's configuration without proper authorization.

The vulnerability is particularly dangerous because the installation component typically has elevated privileges necessary for configuring database connections, administrative accounts, and system settings. When this component lacks proper access restrictions, attackers can potentially reconfigure the entire application, create backdoor accounts, or modify database credentials.

Root Cause

The root cause of this vulnerability is the failure to implement proper access controls on the public/install.php file. The installation script does not adequately verify whether the application has already been installed or whether the requesting user has appropriate administrative privileges. This oversight allows any remote attacker to access the installation endpoint via simple HTTP GET requests.

Common patterns that lead to this type of vulnerability include:

• Missing authentication checks on sensitive endpoints
• Failure to remove or secure installation scripts post-deployment
• Inadequate session validation for privileged operations
• Lack of file-based lock mechanisms to prevent re-installation

Attack Vector

The attack can be initiated remotely through network-based HTTP GET requests targeting the public/install.php endpoint. An attacker does not require any prior authentication or special privileges to exploit this vulnerability. The attack workflow typically involves:

1. Identifying a DSShop installation by fingerprinting the application
2. Sending crafted HTTP GET requests to public/install.php
3. Manipulating installation parameters to modify system configuration
4. Gaining unauthorized access to the application or underlying data

The vulnerability is accessible from the public internet if the DSShop instance is publicly exposed, making it a high-priority target for automated scanning tools and opportunistic attackers. Technical details and additional context are available in the Zhaoj Blog Post and VulDB entry #250432.

Detection Methods for CVE-2024-0412

Indicators of Compromise

• Unexpected HTTP GET requests to /public/install.php in web server access logs
• Changes to application configuration files without authorized administrative action
• Creation of new administrative accounts or modification of existing credentials
• Database connection parameter changes or unexpected database access patterns
• Presence of reinstallation lock files being removed or modified

Detection Strategies

• Monitor web server access logs for requests to install.php from external IP addresses
• Implement Web Application Firewall (WAF) rules to block access to installation endpoints
• Configure intrusion detection systems to alert on access patterns consistent with installation abuse
• Review file integrity monitoring alerts for changes to configuration files

Monitoring Recommendations

• Enable verbose logging on the DSShop application to capture all requests to sensitive endpoints
• Set up real-time alerting for any access attempts to /public/install.php
• Monitor for unauthorized changes to database credentials and admin user accounts
• Implement baseline configuration monitoring to detect drift from expected settings

How to Mitigate CVE-2024-0412

Immediate Actions Required

• Remove or rename the public/install.php file immediately after initial application setup
• Implement IP-based access restrictions to limit access to installation endpoints
• Review access logs for any historical exploitation attempts
• Verify the integrity of application configuration and administrative accounts
• Consider placing the application behind a reverse proxy with enhanced access controls

Patch Information

At the time of this publication, check the vendor's official channels for security patches addressing this vulnerability. Organizations running DeShang DSShop versions 3.0 or 3.1.0 should monitor for updates from csdeshang and apply patches as soon as they become available. Additional information can be found at the VulDB CTI entry.

Workarounds

• Delete or rename public/install.php to prevent access to the installation endpoint
• Add web server configuration rules to deny access to installation-related files
• Implement .htaccess or nginx location blocks to restrict access to sensitive paths
• Use network-level firewalls to limit access to the application from trusted networks only

# Apache .htaccess configuration to block install.php access
<Files "install.php">
    Order Allow,Deny
    Deny from all
</Files>

# Nginx configuration to block install.php access
location ~ /install\.php$ {
    deny all;
    return 403;
}