High severity · published Jan 1, 2026
CVE-2025-69203
Signal K Server Vulnerable to Access Request Spoofing
8.8
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SI
signalk-server · SignalK
< 2.19.0 · source: vendor
SK
Signal K Server · Signalk
before 2.19.0; 2.19.0; 2.19.0; 2.19.0; 2.19.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-69203
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-69203
Release Notes
https://github.com/SignalK/signalk-server/releases/tag/v2.19.0
Exploit
https://github.com/SignalK/signalk-server/security/advisories/GHSA-vfrf-vcj7-wvr8
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