CVE-2024-2646: Netentsec ASG SQL Injection Vulnerability

CVE-2024-2646 Overview

A critical SQL injection vulnerability has been identified in Netentsec NS-ASG Application Security Gateway version 6.3. The vulnerability exists in the file /vpnweb/index.php?para=index and is triggered through improper handling of the check_VirtualSiteId parameter. This flaw allows unauthenticated remote attackers to execute arbitrary SQL commands against the backend database, potentially leading to complete compromise of the application and underlying data.

Critical Impact

This unauthenticated SQL injection vulnerability can be exploited remotely to extract sensitive data, modify database contents, or potentially achieve command execution on the underlying system. The vendor was contacted but did not respond.

Affected Products

• Netentsec NS-ASG Application Security Gateway 6.3
• Netentsec Application Security Gateway (versions prior to patch)

Discovery Timeline

• 2024-03-19 - CVE-2024-2646 published to NVD
• 2025-01-30 - Last updated in NVD database

Technical Details for CVE-2024-2646

Vulnerability Analysis

This SQL injection vulnerability (CWE-89) resides in the VPN web interface of the Netentsec NS-ASG Application Security Gateway. The vulnerable endpoint /vpnweb/index.php?para=index fails to properly sanitize user-supplied input in the check_VirtualSiteId parameter before incorporating it into SQL queries. This lack of input validation allows attackers to inject malicious SQL statements that are then executed by the database engine with the privileges of the application.

The vulnerability is particularly severe because it requires no authentication to exploit. An attacker can remotely craft malicious HTTP requests targeting the vulnerable parameter, enabling unauthorized access to the database. Successful exploitation could result in extraction of sensitive information including user credentials, session tokens, configuration data, and potentially enable privilege escalation or lateral movement within the network.

Root Cause

The root cause is insufficient input validation and improper sanitization of the check_VirtualSiteId parameter in the /vpnweb/index.php endpoint. The application directly incorporates user-controlled input into SQL queries without using parameterized queries or prepared statements, making it susceptible to classic SQL injection attacks.

Attack Vector

The attack vector is network-based, requiring no authentication or user interaction. An attacker can craft HTTP requests to the vulnerable endpoint with specially crafted SQL payloads in the check_VirtualSiteId parameter. The vulnerability can be exploited remotely over the network, and public disclosure indicates that exploit information has been made available, increasing the risk of widespread exploitation.

The vulnerable endpoint accepts the para=index query parameter along with check_VirtualSiteId, which is processed without proper sanitization. Attackers can leverage standard SQL injection techniques including UNION-based, time-based blind, or error-based injection to extract database contents or manipulate data. For detailed technical information, refer to the GitHub PoC Documentation and VulDB #257284 Details.

Detection Methods for CVE-2024-2646

Indicators of Compromise

• HTTP requests to /vpnweb/index.php?para=index containing SQL syntax characters (single quotes, double dashes, UNION, SELECT statements) in the check_VirtualSiteId parameter
• Unusual database queries or errors in application logs indicating injection attempts
• Unexpected database access patterns or data exfiltration from the Application Security Gateway
• Anomalous network traffic to/from the gateway's web management interface

Detection Strategies

• Deploy Web Application Firewall (WAF) rules to detect and block SQL injection patterns targeting the /vpnweb/index.php endpoint
• Implement intrusion detection system (IDS) signatures to identify SQL injection payloads in HTTP traffic destined for Netentsec devices
• Monitor application and database logs for SQL syntax errors, unusual query patterns, or authentication anomalies
• Configure SIEM alerts for multiple failed or suspicious requests to VPN web interface endpoints

Monitoring Recommendations

• Enable detailed HTTP access logging on the Netentsec NS-ASG Application Security Gateway and forward logs to a centralized SIEM
• Monitor for reconnaissance activity targeting the /vpnweb/ directory and related endpoints
• Implement network segmentation to limit exposure of the management interface to trusted networks only
• Review database audit logs for unauthorized SELECT, INSERT, UPDATE, or DELETE operations

How to Mitigate CVE-2024-2646

Immediate Actions Required

• Restrict network access to the /vpnweb/ directory and VPN management interface to trusted IP addresses only
• Deploy a Web Application Firewall (WAF) with SQL injection protection rules in front of the affected appliance
• Monitor logs for exploitation attempts and investigate any suspicious activity
• Consider taking the VPN web interface offline until a patch is available or alternative mitigations are in place
• Contact Netentsec support for guidance on available patches or firmware updates

Patch Information

No official patch has been confirmed from Netentsec at this time. The vendor was contacted about this disclosure but did not respond. Organizations should monitor Netentsec's official channels for security updates and apply any available firmware or software patches immediately upon release. Refer to VulDB #257284 for the latest vulnerability information.

Workarounds

• Implement strict network ACLs to restrict access to the VPN web interface (/vpnweb/) from untrusted networks
• Deploy a reverse proxy or WAF with SQL injection filtering capabilities in front of the gateway
• Disable or restrict access to the /vpnweb/index.php endpoint if not required for operations
• Use VPN or jump hosts to access management interfaces rather than exposing them directly to the internet

# Example: Restrict access to VPN web interface via iptables (Linux firewall)
# Allow only trusted management network (example: 10.0.0.0/24)
iptables -A INPUT -p tcp --dport 443 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP

# Alternative: Use firewall rules on network perimeter to block external access
# to the management interface on ports 80/443