CVE-2026-41893
HIGHSignal K Server is a server application that runs on a central hub in a boat. Prior to version 2.25.0, the HTTP login endpoints (POST /login and POST /signalk/v1/auth/login) are protected by express-rate-limit (default: 100 attempts per 10-minute window, configurable via HTTP_RATE_LIMITS). The WebSocket login path — sending {login: {username, password}} messages over an established WebSocket connection — calls app.securityStrategy.login() directly without any rate limiting. An attacker can bypass HTTP rate limiting entirely by opening a WebSocket connection and attempting unlimited password guesses at the speed bcrypt allows (~20 attempts/sec with 10 salt rounds). This issue has been patched in version 2.25.0.
Published: 5/9/2026Modified: 5/15/2026
References (5)
https://github.com/SignalK/signalk-server/commit/215d81eb700d5419c3396a0fbf23f2e246dfac2dPatchhttps://github.com/SignalK/signalk-server/pull/2568Issue TrackingPatchhttps://github.com/SignalK/signalk-server/releases/tag/v2.25.0ProductRelease Noteshttps://github.com/SignalK/signalk-server/security/advisories/GHSA-vmfm-ch9h-5c7gExploitMitigationhttps://github.com/SignalK/signalk-server/security/advisories/GHSA-vmfm-ch9h-5c7gExploitMitigation