Signal K Server Vulnerable to Access Request Spoofing

Summary

CVE	CVE-2025-69203
State	PUBLISHED
Assigner	GitHub_M
Source Priority	CVE Program / NVD first with legacy fallback
Published	2026-01-01 19:15:54 UTC
Updated	2026-10-01 08:10:00 UTC
Description	Signal K Server is a server application that runs on a central hub in a boat. Versions prior to 2.19.0 of the access request system have two related features that when combined by themselves and with an information disclosure vulnerability enable convincing social engineering attacks against administrators. When a device creates an access request, it specifies three fields: `clientId`, `description`, and `permissions`. The SignalK admin UI displays the `description` field prominently to the administrator when showing pending requests, but the actual `permissions` field (which determines the access level granted) is less visible or displayed separately. This allows an attacker to request `admin` permissions while providing a description that suggests readonly access. The access request handler trusts the `X-Forwarded-For` HTTP header without validation to determine the client's IP address. This header is intended to preserve the original client IP when requests pass through reverse proxies, but when trusted unconditionally, it allows attackers to spoof their IP address. The spoofed IP is displayed to administrators in the access request approval interface, potentially making malicious requests appear to originate from trusted internal network addresses. Since device/source names can be enumerated via the information disclosure vulnerability, an attacker can impersonate a legitimate device or source, craft a convincing description, spoof a trusted internal IP address, and request elevated permissions, creating a highly convincing social engineering scenario that increases the likelihood of administrator approval. Users should upgrade to version 2.19.0 to fix this issue.

Risk And Classification

Primary CVSS: v3.1 8.8 HIGH from [email protected]

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

EPSS: 0.003030000 probability, percentile 0.209260000 (date 2026-10-04)

Problem Types: CWE-290 | CWE-290 CWE-290: Authentication Bypass by Spoofing

Version	Source	Type	Score	Severity	Vector
3.1	[email protected]	Primary	8.8	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`
3.1	[email protected]	Secondary	6.3	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L`
3.1	CNA	DECLARED	6.3	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L`

CVSS v3.1 Breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

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

NVD Known Affected Configurations (CPE 2.3)

Type	Vendor	Product	Version	Update	Edition	Language
Application	Signalk	Signal K Server	All	All	All	All
Application	Signalk	Signal K Server	2.19.0	beta1	All	All
Application	Signalk	Signal K Server	2.19.0	beta2	All	All
Application	Signalk	Signal K Server	2.19.0	beta3	All	All
Application	Signalk	Signal K Server	2.19.0	beta4	All	All

Vendor Declared Affected Products

Source	Vendor	Product	Version	Platforms
CNA	SignalK	Signalk-server	affected < 2.19.0	Not specified

References

Reference	Source	Link	Tags
github.com/SignalK/signalk-server/releases/tag/v2.19.0	[email protected]	github.com	Release Notes
github.com/SignalK/signalk-server/security/advisories/GHSA-vfrf-vcj7-wvr8	[email protected]	github.com	Exploit, Vendor Advisory
CVE Program record	CVE.ORG	www.cve.org	canonical
NVD vulnerability detail	NVD	nvd.nist.gov	canonical, analysis

No vendor comments have been submitted for this CVE.

There are currently no legacy QID mappings associated with this CVE.