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SCA: security update for signalk-server (GHSA-fq56-hvg6-wvm5)

critical Tenable Cloud Security Plugin ID 436540

Description

There are packages installed that are affected by a vulnerability referenced in the following CVE:

 - Signal K Server is a server application that runs on a central hub in a boat. Versions prior to 2.19.0
 expose two features that can be chained together to steal JWT authentication tokens without any prior
 authentication. The attack combines WebSocket-based request enumeration with unauthenticated polling of
 access request status. The first is Unauthenticated WebSocket Request Enumeration: When a WebSocket client
 connects to the SignalK stream endpoint with the `serverevents=all` query parameter, the server sends all
 cached server events including `ACCESS_REQUEST` events that contain details about pending access requests.
 The `startServerEvents` function iterates over `app.lastServerEvents` and writes each cached event to any
 connected client without verifying authorization level. Since WebSocket connections are allowed for
 readonly users (which includes unauthenticated users when `allow_readonly` is true), attackers receive
 these events containing request IDs, client identifiers, descriptions, requested permissions, and IP
 addresses. The second is 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. The `queryRequest` function returns the complete request object including the token field, and
 the REST endpoint uses readonly authentication, allowing unauthenticated access. An attacker has two paths
 to exploit these vulnerabilities. Either the attacker creates their own access request (using the IP
 spoofing vulnerability to craft a convincing spoofed request), then polls their own request ID until an
 administrator approves it, receiving the JWT token; or the attacker passively monitors the WebSocket
 stream to discover request IDs from legitimate devices, then polls those IDs and steals the JWT tokens
 when administrators approve them, hijacking legitimate device credentials. Both paths require zero
 authentication and enable complete authentication bypass. Version 2.19.0 fixes the underlying issues.
 (CVE-2025-68620)

See Also

https://github.com/advisories/GHSA-fq56-hvg6-wvm5

Plugin Details

Severity: Critical

ID: 436540

Version: Revision 1.6

Type: Local

Family: SCA Checks

Published: 1/2/2026

Updated: 7/6/2026

Supported Sensors: Tenable Cloud Security, Tenable Self-Hosted Container Security

Risk Information

VPR

Risk Factor: Medium

Score: 4.3

Percentile: 53.64

Vendor

Vendor Severity: Critical

CVSS v2

Risk Factor: High

Base Score: 9.4

Temporal Score: 7.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:N

CVSS Score Source: CVE-2025-68620

CVSS v3

Risk Factor: Critical

Base Score: 9.1

Temporal Score: 8.2

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 1/2/2026

Vulnerability Publication Date: 1/1/2026

Reference Information

CVE: CVE-2025-68620

cwe: CWE-288