CVE-2026-25851 Overview
CVE-2026-25851 is a critical authentication bypass vulnerability affecting Chargemap's WebSocket endpoints used for the Open Charge Point Protocol (OCPP). The WebSocket endpoints lack proper authentication mechanisms, enabling attackers to perform unauthorized station impersonation and manipulate data sent to the backend. An unauthenticated attacker can connect to the OCPP WebSocket endpoint using a known or discovered charging station identifier, then issue or receive OCPP commands as a legitimate charger.
Critical Impact
This vulnerability allows complete unauthorized control of electric vehicle charging infrastructure, enabling privilege escalation, data manipulation, and potential disruption of charging network operations without any authentication.
Affected Products
- Chargemap chargemap.com (all versions)
Discovery Timeline
- 2026-02-27 - CVE-2026-25851 published to NVD
- 2026-03-05 - Last updated in NVD database
Technical Details for CVE-2026-25851
Vulnerability Analysis
This vulnerability stems from the absence of authentication controls on WebSocket endpoints that handle OCPP communications between charging stations and the backend management system. OCPP (Open Charge Point Protocol) is an application protocol for communication between Electric Vehicle charging stations and a central management system. The vulnerability is classified under CWE-306 (Missing Authentication for Critical Function).
The attack can be executed remotely over the network without requiring any prior authentication or user interaction. Once connected, an attacker gains the ability to issue commands as if they were a legitimate charging station, receive sensitive operational data, and potentially manipulate charging sessions and billing information.
Root Cause
The root cause of this vulnerability is the complete absence of authentication mechanisms on the OCPP WebSocket endpoint. The system accepts connections from any client that knows or can discover a valid charging station identifier, without verifying the identity or authorization of the connecting party. This design flaw allows attackers to impersonate any charging station in the network.
Attack Vector
The attack is network-based and requires no authentication, privileges, or user interaction. An attacker can exploit this vulnerability by following these steps:
- Discovery Phase: Identify or enumerate valid charging station identifiers through reconnaissance or information gathering
- Connection Establishment: Establish a WebSocket connection to the OCPP endpoint using a discovered station identifier
- Impersonation: Send and receive OCPP commands as the impersonated charging station
- Exploitation: Manipulate charging sessions, corrupt backend data, or disrupt charging infrastructure operations
The vulnerability allows for privilege escalation within the charging network, unauthorized control of charging infrastructure, and corruption of charging network data reported to the backend system.
Detection Methods for CVE-2026-25851
Indicators of Compromise
- Unexpected WebSocket connections from unrecognized IP addresses to OCPP endpoints
- Multiple connection attempts using various charging station identifiers from the same source
- Anomalous OCPP command patterns or commands issued outside normal operational hours
- Duplicate station identifiers connecting simultaneously from different network locations
Detection Strategies
- Implement network monitoring to track all WebSocket connections to OCPP endpoints
- Deploy anomaly detection to identify unusual command patterns or connection behaviors
- Monitor for connections from IP ranges outside expected charging station deployments
- Correlate physical charging station status with backend communication logs to detect impersonation
Monitoring Recommendations
- Enable comprehensive logging of all OCPP WebSocket connections including source IP, timestamps, and station identifiers
- Configure alerts for simultaneous connections using the same station identifier from different sources
- Monitor for rapid connection/disconnection patterns that may indicate enumeration attempts
- Review OCPP command logs for unauthorized or unexpected operations
How to Mitigate CVE-2026-25851
Immediate Actions Required
- Contact Chargemap support through their Support Page for vendor-specific guidance
- Implement network-level access controls to restrict OCPP endpoint access to known charging station IP ranges
- Deploy a Web Application Firewall (WAF) or API gateway to add authentication layers
- Review the CISA ICS Advisory #ICSA-26-057-05 for additional guidance
Patch Information
No vendor patch information is currently available in the CVE data. Organizations should contact Chargemap directly through their support channels for remediation guidance. Additional technical details can be found in the GitHub CSAF JSON File published by CISA.
Workarounds
- Implement TLS client certificate authentication for all WebSocket connections to OCPP endpoints
- Deploy network segmentation to isolate charging infrastructure from untrusted networks
- Use VPN tunnels or private network connections between charging stations and backend systems
- Implement IP allowlisting to restrict OCPP endpoint access to known station addresses
- Consider deploying an authentication proxy layer in front of the OCPP WebSocket endpoints
# Example network segmentation configuration (iptables)
# Restrict OCPP WebSocket access to known charging station IP ranges
iptables -A INPUT -p tcp --dport 443 -s 10.20.30.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
