Signal 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.

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Source ID Title
Github GHSA Github GHSA GHSA-vmfm-ch9h-5c7g Signal K Server's WebSocket Login Endpoint Lacks Rate Limiting (Credential Brute-Force)
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Sat, 09 May 2026 20:45:00 +0000

Type Values Removed Values Added
First Time appeared Signalk
Signalk signalk-server
Vendors & Products Signalk
Signalk signalk-server

Sat, 09 May 2026 19:45:00 +0000

Type Values Removed Values Added
Description Signal 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.
Title Signal K Server's WebSocket Login Endpoint Lacks Rate Limiting (Credential Brute-Force)
Weaknesses CWE-307
References
Metrics cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-05-09T19:12:10.082Z

Reserved: 2026-04-22T15:11:54.671Z

Link: CVE-2026-41893

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-05-09T20:16:27.273

Modified: 2026-05-09T20:16:27.273

Link: CVE-2026-41893

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-09T20:30:41Z

Weaknesses