CVE-2026-2621 identifies a SQL injection vulnerability in the Sciyon Koyuan Thermoelectricity Heat Network Management System version 3.0, specifically within the /SISReport/WebReport20/Proxy/AsyncTreeProxy.aspx endpoint. The vulnerability arises from improper sanitization of the PGUID parameter, which an attacker can manipulate to inject malicious SQL commands. This injection flaw allows remote attackers to execute arbitrary SQL queries against the backend database without requiring authentication or user interaction, increasing the attack surface significantly. The vulnerability was publicly disclosed on February 17, 2026, but the vendor Sciyon has not responded to notifications or provided a patch. The CVSS 4.0 base score is 6.9 (medium severity), reflecting the network attack vector, low attack complexity, and no privileges or user interaction needed. The impact includes potential unauthorized disclosure, modification, or deletion of sensitive data related to thermoelectric heat network management, which could disrupt critical infrastructure operations. Although no known exploits are currently active in the wild, the public disclosure and lack of vendor response elevate the urgency for mitigation. The affected system is likely deployed in industrial control environments managing heat distribution, making the vulnerability a concern for operational technology security. Organizations should prioritize detection and containment strategies while awaiting vendor remediation.

The exploitation of this SQL injection vulnerability could have significant consequences for European organizations operating thermoelectric heat network systems. Unauthorized access to the backend database could lead to leakage of sensitive operational data, including infrastructure configurations and usage statistics, potentially aiding further attacks. Data integrity could be compromised by unauthorized modifications or deletions, disrupting heat network management and causing service outages or safety risks. Availability of the system could also be affected if attackers execute destructive queries or cause database corruption. Given the critical nature of heat network management in energy distribution and urban infrastructure, such disruptions could have cascading effects on public services and industrial operations. The lack of vendor response and patch availability increases the risk exposure. European organizations relying on this system must consider the threat to confidentiality, integrity, and availability of their operational technology environments, especially in countries with extensive thermoelectric infrastructure or strategic energy assets.

1. Implement strict input validation and sanitization on all parameters, especially PGUID, to prevent SQL injection. 2. Deploy Web Application Firewalls (WAFs) with custom rules to detect and block SQL injection attempts targeting the vulnerable endpoint. 3. Conduct thorough code reviews and security testing of the affected application components to identify and remediate injection flaws. 4. Monitor database query logs and network traffic for anomalous patterns indicative of injection attacks. 5. Restrict database user permissions to the minimum necessary to limit the impact of any injection exploitation. 6. Segment and isolate the heat network management system within the network to reduce exposure. 7. Establish incident response plans specific to operational technology environments to quickly address potential compromises. 8. Engage with the vendor persistently for patch development or consider alternative solutions if remediation is delayed. 9. Educate operational staff about the risks and signs of exploitation attempts. 10. Consider deploying intrusion detection systems tailored for industrial control systems to enhance monitoring.