Panic in Eclipse KUKSA Databroker gRPC Handler

Executive Summary

CVE-2026-13699 is a vulnerability in Eclipse KUKSA Databroker version 0.6.1. The issue occurs in the `kuksa.val.v2.VAL/PublishValue` gRPC handler, which does not properly validate the existence of the optional `data_point` field in a `PublishValueRequest`.

When a request contains a valid `signal_id` but omits the `data_point` field, the server directly calls `unwrap()` on `request.data_point`. This triggers a panic in the Tokio worker thread, causing the gRPC call to be cancelled. However, the Databroker process itself does not terminate and remains available for subsequent requests.

This vulnerability can be exploited by any client that holds a valid JWT token. Unauthenticated or invalid-token requests are rejected before reaching the vulnerable code path.

Useful 0 Not Useful 0

Detection Guidance

To detect this vulnerability on your network or system, you can check if the Eclipse KUKSA Databroker version 0.6.1 is running. Since the vulnerability is triggered by sending a malformed gRPC request to the kuksa.val.v2.VAL/PublishValue endpoint, you can attempt to reproduce the issue in a controlled environment to confirm its presence.

• Identify the version of Eclipse KUKSA Databroker: Check the installed version to confirm if it is 0.6.1, as this is the affected version.
• Use a gRPC client to send a crafted request: Construct a gRPC request to the kuksa.val.v2.VAL/PublishValue endpoint with a valid signal_id but omit the data_point field. If the server responds with an error or panics (visible in logs), the vulnerability is present.
• Monitor server logs: Check the logs of the Databroker process for panic messages or unexpected terminations of gRPC calls, which may indicate the vulnerability was triggered.

Example command to test the vulnerability (using grpcurl or similar tools):

• grpcurl -plaintext -d '{"signal_id": "valid_signal_id"}' <databroker-address>:<port> kuksa.val.v2.VAL/PublishValue

Replace <databroker-address> and <port> with the actual address and port of the Databroker service. Ensure you have a valid JWT token for authentication, as unauthenticated requests will be rejected before reaching the vulnerable code.

Useful 0 Not Useful 0

Impact Analysis

The vulnerability can impact you in the following ways:

• Denial of Service (DoS): An attacker with a valid JWT token can send crafted requests to trigger a panic in the gRPC handler, causing individual gRPC calls to fail. While the Databroker process remains running, repeated exploitation could degrade service availability.
• Disruption of dependent services: If your system relies on the Eclipse KUKSA Databroker for real-time data processing or communication, the panic-induced failures could disrupt downstream services or applications that depend on it.

The impact is limited to availability, as the vulnerability does not allow unauthorized access to data or system control. The CVSS score of 4.3 (Low) reflects this limited scope.

Useful 0 Not Useful 0

Compliance Impact

The vulnerability may affect compliance with common standards and regulations in the following ways:

• GDPR (General Data Protection Regulation): While this vulnerability does not directly expose personal data, a successful exploitation leading to service disruption could impact the availability of systems processing personal data. GDPR requires organizations to ensure the confidentiality, integrity, and availability of personal data. Prolonged or repeated disruptions could be seen as a failure to meet these requirements.
• HIPAA (Health Insurance Portability and Accountability Act): If the Eclipse KUKSA Databroker is used in a healthcare environment to process or transmit protected health information (PHI), service disruptions caused by this vulnerability could violate HIPAA's requirements for ensuring the availability and integrity of PHI. HIPAA-covered entities must implement safeguards to protect against reasonably anticipated threats to system availability.
• Other standards: Compliance frameworks like ISO 27001 or NIST SP 800-53 emphasize the importance of system availability and resilience. This vulnerability could be considered a gap in meeting controls related to system reliability and incident response.

The specific impact on compliance depends on how the affected software is used within your organization and whether it processes regulated data or supports critical services.

Useful 0 Not Useful 0

Mitigation Strategies

To mitigate this vulnerability, follow these immediate steps:

• Upgrade to a patched version: If a newer version of Eclipse KUKSA Databroker is available that fixes this issue, upgrade to that version immediately.
• Apply temporary workarounds: If upgrading is not immediately possible, restrict access to the gRPC endpoint to trusted clients only. This can be done by configuring network-level restrictions or firewall rules to limit access to the Databroker service.
• Monitor for exploitation attempts: Set up monitoring to detect and alert on malformed gRPC requests targeting the kuksa.val.v2.VAL/PublishValue endpoint, which may indicate an attempt to exploit this vulnerability.
• Review and validate JWT tokens: Ensure that only authorized clients with valid JWT tokens can access the gRPC endpoint, as the vulnerability requires a valid token to be triggered.

Useful 0 Not Useful 0