Signal K set-system-time plugin vulnerable to RCE - Command Injection

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.9 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS

• CVE-2026-23515: 4.52% estimated exploitation activity in the next 30 days; percentile 91.54 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary A Command Injection vulnerability allows authenticated users with write permissions to execute arbitrary shell commands on the Signal K server when the set-system-time plugin is enabled. Unauthenticated users can also exploit this vulnerability if security is disabled on the Signal K server. This occurs due to unsafe construction of shell commands when processing navigation.datetime values received via WebSocket delta messages. Details Product: Signal K set-system-time plugin Repository: https://github.com/SignalK/set-system-time File: index.js, lines 60-71 The vulnerability has three components: 1. Unsanitized Input: The datetime value from navigation.datetime Signal K path is directly interpolated into a shell command without validation 2. Shell Execution: The command is executed via spawn('sh', ['-c', command]), which interprets shell metacharacters 3. Sudo Privileges: The plugin can execute with root privileges if sudo is misconfigured, instructions to limit passwordless…

Published by the source

2 Feb 2026, 18:10 UTC

Last modified by the source

3 Feb 2026, 17:53 UTC

Source last checked

26 Oct 2026, 12:41 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-p8gp-2w28-mhwg

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-p8gp-2w28-mhwg

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-p8gp-2w28-mhwg

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# Patch Next advisory brief: CVE-2026-23515

Advisory: Signal K set-system-time plugin vulnerable to RCE - Command Injection
IDs: CVE-2026-23515, GHSA-p8gp-2w28-mhwg
Record: https://patchnext.com/advisories/cve-2026-23515 (revision 3, source checked 26 Oct 2026, 12:41 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @signalk/set-system-time 1.5.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @signalk/set-system-time: affected < 1.5.0; fixed in 1.5.0

## Suggested inspection (read-only)
- `npm ls @signalk/set-system-time --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @signalk/set-system-time.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-p8gp-2w28-mhwg (GitHub-reviewed advisory GHSA-p8gp-2w28-mhwg lists affected ranges: npm @signalk/set-system-time >=0 <1.5.0)
- Verified: https://osv.dev/vulnerability/GHSA-p8gp-2w28-mhwg (OSV record GHSA-p8gp-2w28-mhwg lists affected ranges: npm @signalk/set-system-time >=0 <1.5.0 (fixed))

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