Vulnerability details
CVE-2026-39320
Signal K Server has an Unauthenticated Regular Expression Denial of Service (ReDoS) via WebSocket Subscription Paths
Official description
Signal K Server is a server application that runs on a central hub in a boat. Versions prior to 2.25.0 are vulnerable to an unauthenticated Regular Expression Denial of Service (ReDoS) attack within the WebSocket subscription handling logic. By injecting unescaped regex metacharacters into the `context` parameter of a stream subscription, an attacker can force the server's Node.js event loop into a catastrophic backtracking loop when evaluating long string identifiers (like the server's self UUID). This results in a total Denial of Service (DoS) where the server CPU spikes to 100% and becomes completely unresponsive to further API or socket requests. Version 2.25.0 contains a fix.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 7.5High | 3.1 | CVEProject cvelistV5 (CNA) (GitHub_M) | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| SignalK | signalk-server | < 2.25.0 | CVEProject cvelistV5 (CNA) |
References and advisories
4- https://github.com/SignalK/signalk-server/pull/2568 x_refsource_MISC
- https://github.com/SignalK/signalk-server/commit/215d81eb700d5419c3396a0fbf23f2e246dfac2d x_refsource_MISC
- https://github.com/SignalK/signalk-server/releases/tag/v2.25.0 x_refsource_MISC
- https://github.com/SignalK/signalk-server/security/advisories/GHSA-7gcj-phff-2884 x_refsource_CONFIRM
Details
- Published
- 2026-04-21
- Last updated
- 2026-04-21
- State
- Published
- Assigner (CNA)
- GitHub_M
Exploit prediction (EPSS)
SSVC assessment (CISA)
- Automatable
- Yes
- Exploitation
- Proof of concept
- Technical impact
- Partial
Weaknesses (CWE)
- CWE-400Uncontrolled Resource Consumption
- CWE-1333Inefficient Regular Expression Complexity