CVE-2025-15103 is a vulnerability identified in the Delta Electronics DVP-12SE11T PLC, categorized under CWE-200 for exposure of sensitive information to unauthorized actors. The core issue is an authentication bypass achieved via partial password disclosure, which means that an attacker can retrieve fragments of the password or authentication tokens, enabling them to circumvent the authentication mechanism. This flaw allows attackers with network access to gain unauthorized control over the device without needing any privileges or user interaction. The vulnerability affects version 0 of the product, with no patches currently available. The CVSS v3.1 score of 8.1 (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H) reflects a high-severity threat with network attack vector, high complexity, no privileges or user interaction required, and full impact on confidentiality, integrity, and availability. The device is typically deployed in industrial control systems, meaning exploitation could lead to unauthorized command execution, data leakage, and disruption of critical processes. Although no exploits have been observed in the wild yet, the potential for significant operational and security impact is high. The vulnerability's presence in a widely used industrial controller raises concerns for sectors relying on automation and control systems.

For European organizations, especially those in manufacturing, energy, utilities, and critical infrastructure sectors, this vulnerability poses a substantial risk. Exploitation could lead to unauthorized access to industrial control systems, resulting in manipulation or disruption of automated processes, data theft, and potential physical damage. The compromise of confidentiality could expose sensitive operational data, while integrity and availability impacts could halt production lines or critical services. Given the reliance on Delta Electronics PLCs in European industrial environments, the threat could affect supply chains and national infrastructure resilience. The lack of patches increases exposure time, and attackers could leverage this vulnerability to gain footholds in networks, escalate privileges, or conduct espionage. The high CVSS score underscores the severity and urgency of addressing this threat to prevent operational and economic damages.

1. Immediately implement strict network segmentation to isolate DVP-12SE11T devices from general IT networks and limit access to trusted management stations only. 2. Employ robust firewall rules and intrusion detection/prevention systems to monitor and block unauthorized access attempts targeting the PLC. 3. Enforce strong access control policies, including multi-factor authentication where possible, to reduce the risk of unauthorized access. 4. Continuously monitor network traffic for anomalies indicative of exploitation attempts, such as unusual authentication requests or partial password disclosures. 5. Coordinate closely with Delta Electronics for timely security advisories and patches; prepare to apply updates as soon as they become available. 6. Conduct thorough security audits and penetration testing focused on industrial control systems to identify and remediate related vulnerabilities. 7. Train operational technology (OT) personnel on this specific threat and best practices for secure device management. 8. Consider deploying compensating controls such as VPNs or encrypted communication channels to protect device access. 9. Maintain up-to-date asset inventories to quickly identify and isolate affected devices in case of incident. 10. Develop and test incident response plans tailored to industrial control system breaches involving this vulnerability.