PT-2026-33877 · Unknown · Signal K Server

Published 2026-04-21 · Updated 2026-04-28 · CVE-2026-39320

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Signal K Server versions prior to 2.25.0

Description An unauthenticated Regular Expression Denial of Service (ReDoS) exists within the WebSocket subscription handling logic. By injecting unescaped regex metacharacters into the context parameter of a stream subscription, an attacker can trigger catastrophic backtracking in the Node.js event loop when the server evaluates long string identifiers. This occurs because the contextMatcher() and pathMatcher() functions in signalk-server/src/subscriptionmanager.ts fail to escape dangerous metacharacters such as +, (, ), ?, [, and ]. Consequently, the server CPU spikes to 100%, rendering the system completely unresponsive to API or socket requests.

Recommendations Update Signal K Server to version 2.25.0.

Exploit

Fix

Resource Exhaustion

DoS

Weakness Enumeration

CWE-400

CWE-1333

Related Identifiers

CVE-2026-39320

GHSA-7GCJ-PHFF-2884

Affected Products

Signal K Server

References · 9

• 🔥 https://github.com/SignalK/signalk-server/security/advisories/GHSA-7gcj-phff-2884 · Exploit
• https://github.com/SignalK/signalk-server/commit/215d81eb700d5419c3396a0fbf23f2e246dfac2d · Patch
• https://github.com/SignalK/signalk-server/pull/2568 · Patch
• https://osv.dev/vulnerability/GHSA-7gcj-phff-2884 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-39320 · Security Note
• https://github.com/SignalK/signalk-server · Note
• https://github.com/SignalK/signalk-server/releases/tag/v2.25.0 · Note
• https://twitter.com/_cvereports/status/2049063821755502823 · Twitter Post
• https://reddit.com/r/VulnMatter/comments/1ssjoms/resumen_diario_de_vulnerabilidades_22042026 · Reddit Post