CVE-2025-27769: Heliox EV Charging Auth Bypass Flaw

CVE-2025-27769 Overview

A vulnerability has been identified in Heliox EV Charging Stations that allows improper access control, potentially enabling an attacker with physical access to reach unauthorized services via the charging cable. This firmware vulnerability affects industrial EV charging infrastructure and could allow unauthorized access to internal services on the affected devices.

Critical Impact
Physical attackers with access to the charging cable can potentially access unauthorized services on vulnerable Heliox EV charging stations, posing risks to charging infrastructure security.

Affected Products

Heliox Flex 180 kW EV Charging Station (All versions < F4.11.1)
Heliox Mobile DC 40 kW EV Charging Station (All versions < L4.10.1)

Discovery Timeline

2026-03-10 - CVE CVE-2025-27769 published to NVD
2026-03-11 - Last updated in NVD database

Technical Details for CVE-2025-27769

Vulnerability Analysis

This vulnerability is classified under CWE-923 (Improper Restriction of Communication Channel to Intended Endpoints), indicating that the affected Heliox EV charging stations fail to properly restrict access to internal services. The physical attack vector means an attacker must have direct access to the charging infrastructure, specifically through the charging cable interface.

The improper access control implementation allows unintended communication pathways to be established, potentially exposing internal services that should not be accessible through the charging interface. While the vulnerability requires physical proximity, it represents a significant concern for public charging infrastructure where physical access may be relatively easy to obtain.

Root Cause

The root cause lies in improper access control mechanisms within the firmware of affected Heliox EV charging stations. The devices fail to adequately restrict which services can be accessed through the charging cable interface, allowing potential exposure of unauthorized services to attackers with physical access.

Attack Vector

Exploitation requires physical access to the charging station, specifically through the charging cable interface. An attacker would need to connect to the charging cable and leverage the improper access controls to reach services that should be restricted. The attack does not require authentication or user interaction, though the physical access requirement significantly limits the attack surface.

The vulnerability allows for limited confidentiality impact on both the vulnerable system and potentially connected downstream systems. No code examples are available for this vulnerability - refer to the Siemens Security Advisory SSA-126399 for detailed technical information.

Detection Methods for CVE-2025-27769

Indicators of Compromise

Unexpected network traffic or connection attempts originating from the charging station's internal interfaces
Anomalous service access patterns or authentication attempts on internal services
Unusual communication activity through the charging cable interface
Logs indicating access to services not normally exposed to charging interfaces

Detection Strategies

Monitor charging station logs for unexpected service access attempts or anomalous connection patterns
Implement network monitoring to detect unusual traffic patterns from charging infrastructure
Deploy intrusion detection systems configured to alert on unauthorized access attempts to internal services
Conduct regular firmware audits to verify charging stations are running patched versions

Monitoring Recommendations

Establish baseline network behavior for charging stations and alert on deviations
Implement physical security monitoring around charging infrastructure
Enable comprehensive logging on charging station management interfaces
Configure alerts for any attempts to access non-standard services through charging interfaces

How to Mitigate CVE-2025-27769

Immediate Actions Required

Upgrade Heliox Flex 180 kW EV Charging Station firmware to version F4.11.1 or later
Upgrade Heliox Mobile DC 40 kW EV Charging Station firmware to version L4.10.1 or later
Implement physical security measures to restrict unauthorized access to charging infrastructure
Review and audit current charging station deployments for affected firmware versions

Patch Information

Siemens has released updated firmware versions that address this vulnerability. Organizations should upgrade to the following minimum versions:

Heliox Flex 180 kW: Update to firmware version F4.11.1 or later
Heliox Mobile DC 40 kW: Update to firmware version L4.10.1 or later

For detailed patch information and firmware downloads, refer to the Siemens Security Advisory SSA-126399.

Workarounds

Implement physical access controls to restrict unauthorized access to charging stations and cables
Deploy network segmentation to isolate charging infrastructure from sensitive networks
Monitor physical access points and implement surveillance around charging stations
Consider temporary service restrictions on charging stations until firmware updates can be applied

bash

# Firmware verification example
# Verify current firmware version on Heliox charging stations
# Access the management interface and check version information
# Flex 180 kW: Ensure version >= F4.11.1
# Mobile DC 40 kW: Ensure version >= L4.10.1