High 8.7Published May 9, 2026

CVE-2026-41893Signal K Server's WebSocket Login Endpoint Lacks Rate Limiting (Credential Brute-Force)

Updated under an hour ago (Oct 27, 2026, 10:50 AM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for signalk-server

Exploited in the last 30 days

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.

CVSS: 8.7 HIGH (v4.0, CNA)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
Weakness (CWE): CWE-307
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: May 14, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

SignalK signalk-server signalk:server (from the name)	before 2.25.0	CNA record
signalk signal_k_server signalk:signal_k_server	before 2.25.0	NVD

References

References

https://github.com/SignalK/signalk-server/security/advisories/GHSA-vmfm-ch9h-5c7g	x-refsource-confirm, exploit, mitigation, vendor-advisory
https://github.com/SignalK/signalk-server/pull/2568	x-refsource-misc, issue-tracking, patch
https://github.com/SignalK/signalk-server/commit/215d81eb700d5419c3396a0fbf23f2e246dfac2d	x-refsource-misc, patch
https://github.com/SignalK/signalk-server/releases/tag/v2.25.0	x-refsource-misc, product, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.