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TI-2026-28309 Aliases CVE-2026-39320GHSA-7gcj-phff-2884

Signal K Server has an Unauthenticated Regular Expression Denial of Service (ReDoS) via WebSocket Subscription Paths

Priority HIGH 72CWE-1333Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-1333.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00427 37th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed signalk-server (SignalK): 2.25.0signalk-server (npm): 2.25.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
SignalKsignalk-serverbefore 2.25.02.25.0Patch availableCNA
—signalk-server (npm)before 2.25.02.25.0Patch availableGHSA-7gcj-phff-2884
  • signalk-server VendorSignalK Affected before 2.25.0 Fixed in 2.25.0 Patch available CNA
  • signalk-server (npm) Vendor— Affected before 2.25.0 Fixed in 2.25.0 Patch available GHSA-7gcj-phff-2884

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:signalk:signal_k_server:*:*:*:*:*:*:*:*before 2.25.0VulnerableSignalK
  • cpe:2.3:a:signalk:signal_k_server:*:*:*:*:*:*:*:* Versions before 2.25.0 Vulnerable ·SignalK

Remediation

  • Fix · CNA signalk-server (SignalK) Fixed in 2.25.0
  • Fix · GHSA-7gcj-phff-2884 signalk-server (npm) Fixed in 2.25.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-39320
  2. 2026-10-03 Alias added: GHSA-7gcj-phff-2884
  3. 2026-10-13 EPSS moved to the 50th–90th percentile
  4. 2026-10-25 EPSS moved to the below the 50th percentile

References

Exploit 1

Patch 2

Advisory 1

Other 2

  • TI-2026-26300 signalk-server: Privilege Escalation by Admin Role Injection via /enableSecurity CVSS 3.1CRITICAL 9.4
  • TI-2025-40835 Signal K Server has Unauthenticated State Pollution leading to Remote Code Execution (RCE) CVSS 3.1CRITICAL 9.7
  • TI-2025-42138 Signal K Server vulnerable to JWT Token Theft via WebSocket Enumeration and Unauthenticated Polling CVSS 3.1CRITICAL 9.1
  • TI-2026-30295 Signal K Server's WebSocket Login Endpoint Lacks Rate Limiting (Credential Brute-Force) CVSS 4.0HIGH 8.7
  • TI-2025-42657 Signal K Server Vulnerable to Access Request Spoofing CVSS 3.1HIGH 8.8
  • TI-2026-18939 RCE - Command Injection in Signal K set-system-time plugin CVSS 3.1CRITICAL 10.0
See all 13 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences