# CVE-2026-123807: Signal K resources API path traversal can disclose the JWT signing secret and enable remote code execution


- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 9 Nov 2026
- **Updated:** 10 Nov 2026
- **Also known as:** GHSA-4xm8-rg9h-jhq2

## What is CVE-2026-123807?

CVE-2026-123807 is a critical vulnerability in @signalk resources-provider, published on 9 Nov 2026. 

### Official description

Signal K Server is a server application that runs on a central hub in a boat. From 2.0.0 until 2.34.0 for Signal K Server and from 1.0.0 until 1.5.3 for @signalk/resources-provider, the v2 REST route GET /signalk/v2/api/resources/:resourceType/:resourceId accepts an unsafe resourceId that can escape the intended resource directory. The route passes the attacker-controlled resourceId through src/api/resources/index.ts to FileStore.getResource() in packages/resources-provider-plugin/src/filestorage.ts without adequate path containment, allowing arbitrary JSON files reachable by the server to be read. Related PUT and DELETE resource operations can write or delete files outside the storage root. Deployments with allow_readonly enabled permit anonymous reads, while other deployments require a readonly user token. Reading security.json exposes the HS256 JWT signing secret and password hashes, allowing an attacker to forge an administrator token. Administrative access to POST /skServer/providers can then create an Execute provider that runs commands with the server process privileges and persists its configuration across restarts. This issue is fixed in Signal K Server 2.34.0 and @signalk/resources-provider 1.5.3.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-123807?

2 open source packages ship an affected version, including @signalk/resources-provider and signalk-server.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `@signalk/resources-provider` | npm | From 1.0.0 | 1.5.3 |
| `signalk-server` | npm | From 2.0.0 | 2.34.0 |

## How do I fix CVE-2026-123807?

Upgrade @signalk/resources-provider to 1.5.3 or later.

## Is CVE-2026-123807 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-123807 exists.

Public exploit code:

- Signal K Server resources API path traversal audit (CVE-2026-123807): read JWT secret, forge admin token, verify RCE (github_poc): https://github.com/qianlijaingshan/signalk-audit

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-123807 and fix it if it is affected.

What it is: CVE-2026-123807 is a critical vulnerability in @signalk resources-provider, published on 9 Nov 2026. 
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-123807 exists.

Affected packages and fixed versions:
- @signalk/resources-provider (npm): affected from 1.0.0; fixed in 1.5.3
- signalk-server (npm): affected from 2.0.0; fixed in 2.34.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-123807/ (Markdown: https://insights.sbomify.com/CVE-2026-123807/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-123807
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-123807
- OSV: https://osv.dev/vulnerability/CVE-2026-123807

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-123807/
Summaries are generated and may contain mistakes; the official description above is the record.