CVE-2026-39320

The record

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.

Affected packages

Related vulnerabilities

• GHSA-7gcj-phff-2884 Signal K Server has an Unauthenticated Regular Expression Denial of Service (ReDoS) via… Same vulnerability
• GHSA-q59x-jc9f-gfqf Signal K Server: Server-Side Request Forgery via Remote Connection Endpoints Also affects signalk-server
• CVE-2026-41893 Signal K Server is a server application that runs on a central hub in a boat. Also affects signalk-server
• GHSA-vmfm-ch9h-5c7g Signal K Server's WebSocket Login Endpoint Lacks Rate Limiting (Credential Brute-Force) Also affects signalk-server
• GHSA-cxj8-ggf2-p57c Signal K Server: OAuth Authorization Code Theft via Unvalidated Host Header in OIDC Flow Also affects signalk-server
• GHSA-gfmv-vh34-h2x5 Signal K Server: Unauthenticated Source Priorities Manipulation Also affects signalk-server
• GHSA-x8hc-fqv3-7gwf Signal K Server: Privilege Escalation by Admin Role Injection via /enableSecurity Also affects signalk-server
• GHSA-qh3j-mrg8-f234 Signal K Server: Arbitrary Prototype Read via `from` Field Bypass Also affects signalk-server