CVE-2026-39320
HIGHSignal K Server <2.25.0 WebSocket Subscriptions - Regular Expression Denial of Service
Title source: manualDescription
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.
References (4)
Core 4
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/SignalK/signalk-server/security/advisories/GHSA-7gcj-phff-2884
X_Refsource_Misc x_refsource_misc
https://github.com/SignalK/signalk-server/pull/2568
X_Refsource_Misc x_refsource_misc
https://github.com/SignalK/signalk-server/commit/215d81eb700d5419c3396a0fbf23f2e246dfac2d
X_Refsource_Misc x_refsource_misc
https://github.com/SignalK/signalk-server/releases/tag/v2.25.0
Scores
CVSS v3
7.5
EPSS
0.0043
EPSS Percentile
33.9%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-1333
CWE-400
Status
published
Products (3)
npm/signalk-server
0 - 2.25.0npm
signalk/signal_k_server
< 2.25.0
SignalK/signalk-server
< 2.25.0
Published
Apr 21, 2026
Tracked Since
Apr 21, 2026