CVE-2025-68620

Comprehensive Technical Analysis of CVE-2025-68620

1. Vulnerability Assessment and Severity Evaluation

CVE ID: CVE-2025-68620

Description: The vulnerability affects Signal K Server, a server application used in marine environments. Versions prior to 2.19.0 are susceptible to a chained attack that allows unauthenticated users to steal JWT authentication tokens. This is achieved through a combination of WebSocket-based request enumeration and unauthenticated polling of access request status.

CVSS Score: 9.1

Severity Evaluation:

• Confidentiality Impact: High
• Integrity Impact: High
• Availability Impact: Medium
• Exploitability: High
• Remediation Level: Official-Fix

The high CVSS score of 9.1 indicates a critical vulnerability that can lead to complete authentication bypass, allowing attackers to gain unauthorized access to the system.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

1. Unauthenticated WebSocket Request Enumeration:

   • Attackers can connect to the SignalK stream endpoint with the serverevents=all query parameter.
   • The server sends all cached server events, including ACCESS_REQUEST events, to any connected client without verifying authorization.
   • This allows attackers to receive details about pending access requests, including request IDs, client identifiers, descriptions, requested permissions, and IP addresses.

2. Unauthenticated Token Polling:

   • The access request status endpoint at /signalk/v1/access/requests/:id returns the full state of an access request without requiring authentication.
   • When an administrator approves a request, the response includes the issued JWT token in plaintext.
   • Attackers can poll this endpoint to retrieve the JWT token once the request is approved.

Exploitation Methods:

1. Active Exploitation:

   • Attackers create their own access request using IP spoofing to craft a convincing request.
   • They then poll their own request ID until an administrator approves it, receiving the JWT token.

2. Passive Exploitation:

   • Attackers passively monitor the WebSocket stream to discover request IDs from legitimate devices.
   • They then poll those IDs and steal the JWT tokens when administrators approve them, hijacking legitimate device credentials.

3. Affected Systems and Software Versions

Affected Systems:

• Signal K Server versions prior to 2.19.0.

Software Versions:

• All versions of Signal K Server before 2.19.0 are vulnerable.

4. Recommended Mitigation Strategies

Immediate Actions:

1. Upgrade to Version 2.19.0:

   • Upgrade Signal K Server to version 2.19.0 or later, which includes fixes for the underlying issues.

2. Disable Unauthenticated Access:

   • Ensure that the allow_readonly configuration is set to false to prevent unauthenticated WebSocket connections.

3. Monitor and Audit:

   • Implement monitoring and auditing of access requests and approvals to detect any suspicious activity.

Long-Term Strategies:

1. Regular Security Audits:

   • Conduct regular security audits and vulnerability assessments of the Signal K Server and related systems.

2. Access Control Policies:

   • Implement strict access control policies and ensure that only authorized users can approve access requests.

3. Network Segmentation:

   • Segment the network to isolate critical systems and reduce the attack surface.

5. Impact on Cybersecurity Landscape

Impact:

• Authentication Bypass: The vulnerability allows attackers to bypass authentication mechanisms, gaining unauthorized access to sensitive systems and data.
• Credential Theft: The ability to steal JWT tokens can lead to credential theft, enabling attackers to impersonate legitimate users and devices.
• Marine Cybersecurity: This vulnerability highlights the importance of cybersecurity in marine environments, where systems like Signal K Server are critical for navigation and communication.

Broader Implications:

• Supply Chain Security: The vulnerability underscores the need for robust supply chain security, as compromised marine systems can have cascading effects on logistics and transportation.
• Regulatory Compliance: Organizations must ensure compliance with maritime cybersecurity regulations and standards to mitigate such risks.

6. Technical Details for Security Professionals

Technical Analysis:

1. WebSocket Request Enumeration:

   • The startServerEvents function iterates over app.lastServerEvents and writes each cached event to any connected client without verifying authorization.
   • This allows unauthenticated users to receive sensitive information about pending access requests.

2. Unauthenticated Token Polling:

   • The queryRequest function returns the complete request object, including the token field, without requiring authentication.
   • The REST endpoint uses readonly authentication, allowing unauthenticated access to the access request status.

Code Snippets (Hypothetical):

// Vulnerable code snippet for WebSocket Request Enumeration
function startServerEvents(client) {
    app.lastServerEvents.forEach(event => {
        client.send(event);
    });
}

// Vulnerable code snippet for Unauthenticated Token Polling
function queryRequest(req, res) {
    const request = getRequestById(req.params.id);
    res.json(request);
}

Fix Implementation:

• Ensure proper authorization checks before sending cached events to WebSocket clients.
• Require authentication for accessing the access request status endpoint.

Conclusion: CVE-2025-68620 is a critical vulnerability that underscores the need for robust authentication and authorization mechanisms in marine cybersecurity systems. Immediate mitigation through software updates and strict access control policies is essential to protect against unauthorized access and credential theft.