NVD / CVE Program· CNA GitHub_M

CVE-2026-25228: SignalK Server has Path Traversal leading to information disclosure

MediumCVSS 4.3 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 17/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.42% (FIRST EPSS).
Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
Fixed version: SignalK signalk-server 2.20.3.

Low priority for now. Upgrade to SignalK signalk-server 2.20.3 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Signal K Server is a server application that runs on a central hub in a boat. Prior to 2.20.3, a path traversal vulnerability in SignalK Server's applicationData API allows authenticated users on Windows systems to read, write, and list arbitrary files and directories on the filesystem. The validateAppId() function blocks forward slashes (/) but not backslashes (\), which are treated as directory separators by path.join() on Windows. This enables attackers to escape the intended applicationData directory. This vulnerability is fixed in 2.20.3.

Path traversal

GHSA-vrhw-v2hw-jffx

Published: Feb 2, 2026
Updated: Jun 17, 2026
EPSS: 0.4% · 37th percentile
CWE: CWE-22

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 17 / 40 · 4.3 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.4%

CISA SSVC decision

Exploitation: proof of concept
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: 4.3
CNA · GitHub_M: 5.0; 0.7 point gap

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
signalk	signal k server	cpe:2.3:a:signalk:signal_k_server
microsoft	windows	cpe:2.3:o:microsoft:windows

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

SignalK signalk-server
- < 2.20.3affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

signalk signal k serverbefore 2.20.3

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
npm	signalk-server	before 2.20.3	2.20.3

Same product

signalk: all records

Other highest-scoring records for the same primary product.

CVE-2025-66398Signal K Server has Unauthenticated State Pollution leading to Remote Code Execution (RCE)
41Plan
CVE-2026-33950signalk-server: Privilege Escalation by Admin Role Injection via /enableSecurity
37Monitor
CVE-2026-23515RCE - Command Injection in Signal K set-system-time plugin
36Monitor

Published before and after this one in the same product

← EarlierCVE-2025-68620Jan 1, 2026 · Signal K Server vulnerable to JWT Token Theft via WebSocket Enumeration and Unauthenticated Polling
36Monitor
← EarlierCVE-2025-69203Jan 1, 2026 · Signal K Server Vulnerable to Access Request Spoofing
35Monitor
Later →CVE-2026-33951Apr 2, 2026 · signalk-server: Unauthenticated Source Priorities Manipulation
27Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
SignalK signalk-server	2.20.3 · description	Vendor (CNA)
npm:signalk-server	2.20.3	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

SignalK/signalk-servercommit 9bcf61c

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

CVE-2025-6862032 days apartSignal K Server vulnerable to JWT Token Theft via WebSocket Enumeration and Unauthenticated Polling
36Monitor
CVE-2025-6920332 days apartSignal K Server Vulnerable to Access Request Spoofing
35Monitor

Not on record for this CVE: EPSS history · researcher credit · public bounty program.

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: low · data can be read
Integrity: none
Availability: none

Attack vector: Network
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: Low
Integrity impact: None
Availability impact: None

Weakness class (CWE)

CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

nvd-primary

Root cause

A user-supplied file name is joined with the allowed directory, but the result is never checked to confirm it is still inside that directory.

The bug in code

The whole CWE-22 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1const file = path.join(ROOT, req.query.name);
2res.sendFile(file);

Fixed

1const file = path.resolve(ROOT, req.query.name);
2if (!file.startsWith(ROOT + path.sep)) {
3  return res.sendStatus(400);
4}
5res.sendFile(file);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log (1)

Fix✗ → ✓Sep 28, 2026, 10:47 PM UTC

For records you follow, these changes also arrive as notifications. →

References

github.com/SignalK/signalk-server/commit/9bcf61c8fe2cb8a40998b913a02fb64dff9e86c7

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records