CVE-2025-64125 identifies a critical security vulnerability in the Nuvation Energy nCloud VPN Service, specifically categorized under CWE-441, which involves unintended proxy or intermediary functionality. This vulnerability allows network boundary bridging, meaning that the VPN service could inadvertently act as a proxy or intermediary, potentially exposing internal network traffic to unauthorized interception or manipulation. The flaw could be exploited remotely over the network without requiring elevated privileges, though some user interaction is necessary, which might involve initiating a VPN connection or similar action. The CVSS 4.0 vector indicates a network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:L), and user interaction (UI:P), with high impact on confidentiality, integrity, and availability (VC:H/VI:H/VA:H). The scope is partial (S:P), indicating that the vulnerability affects components beyond the initially vulnerable component. The vulnerability was publicly disclosed on January 3, 2026, with a fix released on December 1, 2025. No known exploits have been reported in the wild, suggesting that exploitation may be complex or not yet weaponized. The vulnerability's nature could allow attackers to intercept or redirect VPN traffic, potentially leading to data leakage, session hijacking, or man-in-the-middle attacks, severely compromising secure communications. Since the nCloud VPN Service is used to secure industrial and energy sector communications, this vulnerability poses a significant risk to critical infrastructure environments.

For European organizations, especially those in critical infrastructure sectors such as energy, manufacturing, and utilities, this vulnerability poses a severe risk. The nCloud VPN Service is likely used to secure sensitive communications and remote access to operational technology (OT) and industrial control systems (ICS). Exploitation could lead to unauthorized access to internal networks, interception of confidential data, manipulation of control commands, and disruption of services. This could result in operational downtime, financial losses, regulatory penalties, and damage to reputation. Given the high CVSS score and the critical nature of the vulnerability, attackers could leverage this flaw to conduct espionage, sabotage, or ransomware attacks. The fact that no user action is required to mitigate the issue after patching simplifies remediation but also means unpatched systems remain highly vulnerable. European organizations with extensive VPN deployments and reliance on Nuvation Energy's solutions are at heightened risk.

Organizations should immediately verify their use of the Nuvation Energy nCloud VPN Service and ensure that all instances are updated to the patched version released on December 1, 2025. Since end users do not need to take action beyond updating, IT and security teams must prioritize patch management and deployment. Network segmentation should be enforced to limit the exposure of critical systems accessible via the VPN. Monitoring VPN traffic for anomalies indicative of proxy or intermediary misuse can help detect exploitation attempts. Implementing multi-factor authentication (MFA) for VPN access can reduce the risk of unauthorized use. Additionally, organizations should review VPN configuration settings to disable any unintended proxy or bridging features if configurable. Conducting penetration testing and vulnerability assessments focused on VPN infrastructure will help identify residual risks. Finally, maintaining up-to-date incident response plans tailored to VPN compromise scenarios is essential.