CVE-2025-69203 Signal K Server Vulnerable to Access Request Spoofing
Attackers can spoof IP addresses and device names to trick administrators into granting elevated access permissions via social engineering.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2025-69203?
CVE-2025-69203 is a medium-severity authentication bypass vulnerability in signalk-server, published on 1 Jan 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-290
Which versions are affected by CVE-2025-69203?
2 open source packages ship an affected version, including signalk-server. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
signalk-server npm | All versions | 2.19.0 |
signalk-server npm | All versions | 2.19.0 |
Products include Signalk Signal K Server.
How do I fix CVE-2025-69203?
Upgrade signalk-server to 2.19.0 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2025-69203 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-69203 exists.
Other vulnerabilities in signalk-server
- CVE-2026-23515 RCE - Command Injection in Signal K set-system-time plugin
- CVE-2025-66398 Signal K Server has Unauthenticated State Pollution leading to Remote Code Execution (RCE)
- CVE-2026-33950 signalk-server: Privilege Escalation by Admin Role Injection via /enableSecurity
- CVE-2025-68620 Signal K Server vulnerable to JWT Token Theft via WebSocket Enumeration and Unauthenticated Polling
- CVE-2026-41893 Signal K Server's WebSocket Login Endpoint Lacks Rate Limiting (Credential Brute-Force)
Sources
Also known as GHSA-vfrf-vcj7-wvr8.