CVE-2025-34245 is a SQL injection vulnerability identified in Advantech WebAccess/VPN, a product widely used for industrial automation and secure remote access. The flaw exists in the AjaxStandaloneVpnClientsController.ajaxAction() method, which processes datatable search parameters without proper sanitization or neutralization of special SQL elements. This improper input handling allows an authenticated user with low privileges (observer role) to craft malicious SQL payloads that can manipulate backend database queries. As a result, attackers can extract sensitive information from the database, potentially exposing credentials, configuration data, or other confidential information. The vulnerability is remotely exploitable without user interaction and does not require elevated privileges beyond observer access, increasing its risk profile. The CVSS 4.0 base score of 5.3 reflects medium severity, considering the network attack vector, low complexity, and limited scope of impact (confidentiality and integrity). No patches were linked at the time of disclosure, but upgrading to version 1.1.5 or later is advised. No known exploits have been reported in the wild, but the vulnerability's nature makes it a candidate for targeted attacks against industrial and critical infrastructure environments using Advantech products.

For European organizations, this vulnerability could lead to unauthorized disclosure of sensitive operational data, potentially compromising industrial control systems and VPN configurations. Exposure of database contents may facilitate further attacks such as privilege escalation, lateral movement, or disruption of industrial processes. Given Advantech's prominence in industrial automation sectors, organizations in manufacturing, energy, transportation, and critical infrastructure are particularly at risk. Data breaches could result in operational downtime, regulatory penalties under GDPR due to exposure of personal or sensitive data, and reputational damage. The ability for low-privileged users to exploit this vulnerability increases insider threat risks and complicates access control strategies. The medium severity rating suggests that while immediate catastrophic impact is unlikely, the vulnerability poses a significant risk if left unmitigated, especially in environments where WebAccess/VPN is integrated with critical systems.

1. Upgrade Advantech WebAccess/VPN to version 1.1.5 or later where the vulnerability is fixed. 2. Restrict observer user roles strictly to necessary personnel and review user privileges regularly to minimize attack surface. 3. Implement input validation and sanitization at the application layer to prevent SQL injection, including the use of parameterized queries or prepared statements. 4. Employ Web Application Firewalls (WAFs) with custom rules to detect and block suspicious SQL injection patterns targeting the vulnerable endpoint. 5. Monitor database query logs and application logs for anomalous or unexpected queries that may indicate exploitation attempts. 6. Conduct regular security assessments and penetration testing focused on web application vulnerabilities in industrial control system environments. 7. Isolate the WebAccess/VPN management interfaces from general network access where possible, using network segmentation and strict firewall rules. 8. Educate administrators and users about the risks of SQL injection and the importance of applying security updates promptly.