Vulnerability · Published Jan 1, 2026 · Assigned by GitHub_M

CVE-2025-66398Signal K Server has Unauthenticated State Pollution leading to Remote Code Execution (RCE)

Critical 9.7

In plain English

A critical-severity OS command injection in signalk-server from SignalK. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 19.9% (higher than 97% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)9.7Critical

Exploit odds (30 days)19.9%top 2.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack tooling1Public PoC

Official description

Signal K Server is a server application that runs on a central hub in a boat. Prior to version 2.19.0, an unauthenticated attacker can pollute the internal state (`restoreFilePath`) of the server via the `/skServer/validateBackup` endpoint. This allows the attacker to hijack the administrator's "Restore" functionality to overwrite critical server configuration files (e.g., `security.json`, `package.json`), leading to account takeover and Remote Code Execution (RCE). Version 2.19.0 patches this vulnerability.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	signalk-server	2.19.0	GHSA-w3x5-7c4c-66p9

Affected products (as reported)

Vendor	Product	Versions
SignalK	signalk-server	< 2.19.0

Weakness: CWE-78, CWE-913 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

References

https://github.com/SignalK/signalk-server/security/advisories/GHSA-w3x5-7c4c-66p9 x_refsource_CONFIRM
https://github.com/SignalK/signalk-server/releases/tag/v2.19.0 x_refsource_MISC