Auth bypass in Signalk Signal K Server
CVE-2026-33951
Signal K Server is a server application that runs on a central hub in a boat. Prior to version 2.24.0-beta.1, the SignalK Server exposes an unauthenticated HTTP endpoint that allows remote attackers to modify navigation data source priorities. This endpoint, accessible via PUT /signalk/v1/api/sourcePriorities, does not enforce authentication or authorization checks and directly assigns user-controlled input to the server configuration. As a result, attackers can influence which GPS, AIS, or other sensor data sources are trusted by the system. The changes are immediately applied and persisted to disk, allowing the manipulation to survive server restarts. This issue has been patched in version 2.24.0-beta.1.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.003 (25.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 25.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.003 · change: -0.002
Affected products
- Signalk Signal K Server
- Signalk Signalk-Server — versions < 2.24.0-beta.1
Weakness classification (CWE)
References
- github.com/SignalK/signalk-server/security/advisories/GHSA-gfmv-vh34-h2x5 (Vendor Advisory)
- github.com/SignalK/signalk-server/releases/tag/v2.24.0-beta.1 (Product, Release Notes)
Frequently asked questions
- What is CVE-2026-33951?
- CVE-2026-33951 is a high-severity vulnerability in Signalk Signal K Server, classified under Improper Access Control. CVSS score: 7.5/10. Published 2026-04-02.
- How severe is CVE-2026-33951?
- High severity. CVSS v3 base score is 7.5 out of 10.