CVE-2026-25778: Swtchenergy Auth Bypass Vulnerability

CVE-2026-25778 Overview

CVE-2026-25778 is a session hijacking vulnerability in the Swtch Energy WebSocket backend that manages electric vehicle charging station communications. The WebSocket backend uses charging station identifiers to uniquely associate sessions but allows multiple endpoints to connect using the same session identifier. This implementation results in predictable session identifiers and enables session hijacking or shadowing, where the most recent connection displaces the legitimate charging station and receives backend commands intended for that station.

This vulnerability may allow unauthorized users to authenticate as other users or enable a malicious actor to cause a denial-of-service condition by overwhelming the backend with valid session requests. The flaw represents a critical security gap in Industrial Control Systems (ICS) infrastructure used for EV charging networks.

Critical Impact

Attackers can hijack charging station sessions to intercept backend commands, impersonate legitimate stations, or cause service disruptions across EV charging infrastructure.

Affected Products

• Swtch Energy swtchenergy.com platform
• WebSocket backend for charging station communications
• All versions prior to security patch (check vendor for specific versions)

Discovery Timeline

• 2026-02-27 - CVE CVE-2026-25778 published to NVD
• 2026-03-05 - Last updated in NVD database

Technical Details for CVE-2026-25778

Vulnerability Analysis

This vulnerability is classified under CWE-613 (Insufficient Session Expiration), which indicates that the application does not properly invalidate or expire session identifiers when new connections are established with the same credentials. In the context of the Swtch Energy WebSocket backend, charging station identifiers are used as the basis for session management.

The core issue lies in the session handling architecture where the backend permits multiple WebSocket connections to utilize identical charging station identifiers without proper validation or connection arbitration. When a new connection is established using an existing station's identifier, the backend simply transfers the active session to the new endpoint rather than rejecting the duplicate connection or implementing proper session locking mechanisms.

This design enables an attacker who can predict or obtain a valid charging station identifier to establish a connection that effectively hijacks the legitimate station's session. The original station loses its connection context, and all subsequent backend commands—including charging session management, authentication tokens, and operational directives—are routed to the attacker's endpoint.

Root Cause

The root cause is insufficient session management in the WebSocket backend that fails to enforce session uniqueness. The system uses predictable charging station identifiers as session tokens without implementing proper session binding, validation of connection origin, or mutual authentication between the backend and charging stations. This allows session identifiers to be reused across different endpoints without proper verification.

Attack Vector

The attack vector is network-based, requiring no authentication or user interaction. An attacker with network access to the WebSocket backend can enumerate or predict charging station identifiers and establish connections that displace legitimate stations. The attack can be executed remotely against any exposed Swtch Energy backend infrastructure.

The attack sequence involves:

1. Reconnaissance to identify valid charging station identifiers through enumeration or traffic analysis
2. Establishing a WebSocket connection to the backend using a targeted station's identifier
3. The attacker's connection displaces the legitimate station's session
4. Backend commands intended for the legitimate station are now received by the attacker
5. Optionally, the attacker can flood the backend with session requests to cause denial-of-service

For additional technical details, refer to the CISA ICS Advisory ICSA-26-057-06 and the GitHub CSAF Data File.

Detection Methods for CVE-2026-25778

Indicators of Compromise

• Multiple WebSocket connections from different IP addresses using identical charging station identifiers
• Unusual session disconnection patterns for charging stations followed by reconnections from new endpoints
• High volume of session establishment requests that may indicate enumeration attempts
• Charging stations reporting unexpected disconnections or command inconsistencies

Detection Strategies

• Monitor WebSocket connection logs for duplicate station identifier usage from different source IPs
• Implement anomaly detection for session displacement events where legitimate stations are disconnected
• Alert on rapid enumeration patterns in connection attempts using sequential or predictable identifiers
• Correlate network traffic analysis with charging station operational logs to identify impersonation

Monitoring Recommendations

• Deploy network monitoring at WebSocket backend ingress points to track connection metadata
• Configure SIEM rules to detect multiple concurrent sessions using identical station credentials
• Establish baseline connection patterns for charging stations and alert on deviations
• Log all WebSocket handshake events with full connection details for forensic analysis

How to Mitigate CVE-2026-25778

Immediate Actions Required

• Contact Swtch Energy through their contact page to obtain security patches and guidance
• Implement network segmentation to restrict access to WebSocket backend endpoints
• Deploy Web Application Firewall (WAF) rules to rate-limit connection attempts per identifier
• Enable enhanced logging on all WebSocket connections for incident detection

Patch Information

Consult the CISA ICS Advisory ICSA-26-057-06 for official vendor guidance and patch availability. Contact Swtch Energy directly for the latest security updates addressing this session management vulnerability.

Workarounds

• Implement network-level access controls to restrict WebSocket backend access to known charging station IP ranges
• Deploy mutual TLS (mTLS) authentication between charging stations and the backend to verify station identity
• Add monitoring and alerting for session displacement events as an interim detection measure
• Consider placing the WebSocket backend behind a VPN or private network until patches are applied

# Example firewall configuration to restrict WebSocket backend access
# Adjust IP ranges to match your charging station network

# Allow connections only from known charging station networks
iptables -A INPUT -p tcp --dport 443 -s 10.10.0.0/16 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 192.168.100.0/24 -j ACCEPT

# Drop all other connections to WebSocket backend port
iptables -A INPUT -p tcp --dport 443 -j DROP

# Enable connection logging for audit purposes
iptables -A INPUT -p tcp --dport 443 -j LOG --log-prefix "WS-BACKEND: "