CVE-2025-27769 identifies a vulnerability in Siemens Heliox Flex 180 kW and Heliox Mobile DC 40 kW electric vehicle charging stations, specifically in versions prior to F4.11.1 and L4.10.1. The issue stems from improper restriction of communication channels (CWE-923), which means the devices do not adequately enforce access controls on the communication interfaces accessible via the charging cable. This flaw allows an attacker with physical access to the charging cable to reach unauthorized internal services that should be protected. The vulnerability does not require authentication or user interaction, increasing the risk of exploitation by anyone physically near the device. However, the attack vector is limited to physical proximity, and the CVSS 3.1 score is low (2.6), reflecting limited impact primarily on confidentiality with no direct impact on integrity or availability. The scope is considered changed (S:C) because the vulnerability could affect components beyond the initially intended communication endpoints. No patches or exploits are currently publicly available, but the issue highlights the importance of secure communication channel enforcement in EV charging infrastructure, which is critical for operational security and privacy. Siemens has reserved the CVE and published the vulnerability details, but no patch links are provided yet.

The primary impact of this vulnerability is the potential unauthorized access to internal services of Siemens EV charging stations, which could lead to information disclosure. While the confidentiality impact is low, exposure of sensitive operational data or configuration details could aid attackers in further attacks or reconnaissance. The lack of impact on integrity and availability means the charging stations' core functionality remains intact, reducing the risk of service disruption. However, given the growing deployment of EV infrastructure worldwide, any compromise of charging stations could undermine user trust and operational security. Organizations operating Siemens Heliox charging stations may face increased risk if attackers gain physical access to the charging cables, especially in public or semi-public locations. The vulnerability could also have regulatory implications if sensitive data is exposed. Overall, the threat is limited by the need for physical access and the low severity, but it should not be ignored due to the critical role of EV charging infrastructure in energy and transportation sectors.

To mitigate CVE-2025-27769, organizations should implement strict physical security controls around Siemens Heliox EV charging stations to prevent unauthorized physical access to the charging cables. Deploying surveillance, access barriers, or secure enclosures can reduce the risk of exploitation. Siemens customers should monitor official communications for firmware updates addressing this vulnerability and apply patches promptly once available. Network segmentation of EV charging infrastructure can limit the exposure of internal services even if the communication channel is accessed. Additionally, organizations can conduct regular security assessments of their EV charging stations to detect unauthorized access attempts. Implementing logging and alerting mechanisms on the charging stations or associated management systems can help identify suspicious activities. Finally, educating staff and users about the risks of physical tampering with charging stations can enhance overall security posture.