CVE-2026-4586: Chat2DB Auth Bypass Vulnerability

CVE-2026-4586 Overview

A vulnerability has been discovered in CodePhiliaX Chat2DB versions up to 0.3.7 that allows for unrestricted file upload through the JDBC Driver Upload functionality. The vulnerability exists in the Upload function within the JdbcDriverController.java file located at chat2db-server/chat2db-server-web/chat2db-server-web-api/src/main/java/ai/chat2db/server/web/api/controller/driver/. This improper access control flaw enables remote attackers to upload arbitrary files to the server without proper validation or restrictions.

Critical Impact

Remote attackers with low-level privileges can exploit this unrestricted file upload vulnerability to potentially execute arbitrary code, compromise server integrity, or establish persistent access to affected Chat2DB instances.

Affected Products

• CodePhiliaX Chat2DB versions up to and including 0.3.7
• Chat2DB Server Web API component
• JDBC Driver Upload functionality

Discovery Timeline

• 2026-03-23 - CVE-2026-4586 published to NVD
• 2026-03-23 - Last updated in NVD database

Technical Details for CVE-2026-4586

Vulnerability Analysis

This vulnerability is classified under CWE-284 (Improper Access Control), indicating that the application fails to properly restrict access to a resource or fails to validate permissions before allowing file uploads. The affected component is the JDBC Driver Upload feature, which is designed to allow administrators to upload custom database drivers. However, due to improper access control mechanisms, the Upload function does not adequately validate the type, content, or destination of uploaded files.

The vulnerability can be exploited remotely over the network by authenticated users with low privileges. Successful exploitation could lead to partial compromise of confidentiality, integrity, and availability of the affected system. The exploit has been publicly disclosed, and proof-of-concept information is available, increasing the risk of active exploitation.

Root Cause

The root cause of this vulnerability lies in the inadequate implementation of access control and input validation within the JdbcDriverController.java file. The Upload function fails to:

1. Properly validate user permissions before accepting file uploads
2. Restrict the types of files that can be uploaded
3. Sanitize file names and content to prevent malicious uploads
4. Implement proper file storage location restrictions

This allows attackers to bypass intended security restrictions and upload files that may include executable code, web shells, or other malicious content.

Attack Vector

The attack can be initiated remotely over the network by an authenticated user with minimal privileges. The attacker targets the JDBC Driver Upload endpoint and submits a specially crafted request containing a malicious file. Due to the lack of proper access control and file validation, the server accepts and stores the file without appropriate checks.

The exploitation mechanism involves manipulating the file upload request to the vulnerable endpoint. Technical details and proof-of-concept information are available through the Feishu Document Link and VulDB entry #352432. The vendor was contacted about this disclosure but did not respond.

Detection Methods for CVE-2026-4586

Indicators of Compromise

• Unexpected files appearing in JDBC driver upload directories
• Unusual file types or extensions in driver storage locations
• Web shell signatures or suspicious executable files on the server
• Abnormal network traffic patterns to the JDBC driver upload endpoint

Detection Strategies

• Monitor HTTP requests to /api/controller/driver/ endpoints for suspicious upload activity
• Implement file integrity monitoring on directories where JDBC drivers are stored
• Review application logs for unauthorized or anomalous file upload attempts
• Deploy web application firewall rules to detect unrestricted file upload patterns

Monitoring Recommendations

• Enable detailed logging for all file upload operations in Chat2DB
• Set up alerts for uploads of non-JAR file types to the JDBC driver directory
• Monitor for creation of unexpected files with executable permissions
• Implement real-time monitoring of the affected controller endpoint

How to Mitigate CVE-2026-4586

Immediate Actions Required

• Upgrade Chat2DB to a patched version when available from CodePhiliaX
• Restrict network access to the JDBC Driver Upload functionality to trusted administrators only
• Implement additional authentication controls for the driver upload endpoint
• Review and remove any suspicious files that may have been uploaded to the system

Patch Information

At the time of publication, no official patch has been released by CodePhiliaX. The vendor was contacted early about this disclosure but did not respond. Organizations should monitor the official Chat2DB repository and VulDB entry for updates regarding security patches.

Workarounds

• Disable the JDBC Driver Upload feature if not required for operations
• Implement network-level access controls to restrict access to the vulnerable endpoint
• Deploy a web application firewall with rules to block suspicious file upload attempts
• Use reverse proxy configurations to require additional authentication for sensitive endpoints

# Example: Restrict access to JDBC driver upload endpoint via nginx
location /api/controller/driver/ {
    # Allow only from trusted admin IP addresses
    allow 10.0.0.0/8;
    deny all;
    
    # Require additional authentication
    auth_basic "Admin Access Required";
    auth_basic_user_file /etc/nginx/.htpasswd;
}