CVE-2026-41893Public exploitNetwork attack vector

Credential brute-forcing via unthrottled WebSocket login

Published May 9, 2026 · Updated May 9, 2026

Improper login-attempt restriction in Signal K Server before 2.25.0 allows remote attackers to brute-force credentials over WebSocket. The processLoginRequest function in src/interfaces/ws.ts calls app.securityStrategy.login() directly without throttling or attempt tracking. Security must be enabled and the WebSocket service reachable; one connection can submit unlimited guesses at bcrypt-limited speed, enabling account compromise when a password is found.

CVSS severity8.7
High
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper login-attempt restriction in Signal K Server before 2.25.0 allows remote attackers to brute-force credentials over WebSocket. The processLoginRequest function in src/interfaces/ws.ts calls app.securityStrategy.login() directly without throttling or attempt tracking. Security must be enabled and the WebSocket service reachable; one connection can submit unlimited guesses at bcrypt-limited speed, enabling account compromise when a password is found.

The record

CVE
CVE-2026-41893
Published
May 9, 2026
Updated
May 9, 2026
Vendor
Signal K
Product
Signal K Server
Classifications
CWE-307, T1110
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 9, 2026CVE publishedPublication date reported by the CVE source.
  2. May 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 2.25.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Signal K · Signal K Serverversion=< 2.25.0

Published CVSS scores

8.7GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-307Improper Restriction of Excessive Authentication Attempts
T1110Brute Force

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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