CVE-2025-66398

Name: CVE-2025-66398
Creator: NVD / NIST
Published: 2026-01-01T18:15:40.55+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 17.93%

Last modified Jun 17, 2026

CVE-2025-66398 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. 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. EPSS estimates a 17.93% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS Probability

17.93%

96.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Signalk	Signal K Server	< 2.19.0

References

https://github.com/SignalK/signalk-server/releases/tag/v2.19.0Release Notes
https://github.com/SignalK/signalk-server/security/advisories/GHSA-w3x5-7c4c-66p9Exploit, Vendor Advisory

Timeline

Published: Jan 1, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2025-66398?

How severe is CVE-2025-66398?

CVE-2025-66398 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 17.93% probability of exploitation in the next 30 days.

How do I fix CVE-2025-66398?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2025-66398?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST