Cyber Resilience

CVE-2026-23515

RCE in Signalk Signal K Server ≤ 1.5.0

Published
02 February 2026
Modified
27 February 2026
Patch / advisory
CVSS Score v3.1 9.9
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.042 90th percentile
Risk Priority 77 floored blend · peak EPSS

Summary

CVE-2026-23515 is a critical-severity OS Command Injection (CWE-78) vulnerability in Signalk Signal K Server. Its CVSS base score is 9.9 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 10% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-23515 is a command injection vulnerability (CWE-78) affecting Signal K Server versions prior to 1.5.0. Signal K Server is a server application that runs on a central hub in a boat. The issue stems from unsafe construction of shell commands when processing navigation.datetime values received via WebSocket delta messages, specifically when the set-system-time plugin is enabled.

Authenticated users with write permissions can exploit this vulnerability to execute arbitrary shell commands on the Signal K server. Unauthenticated users can also exploit it if security is disabled on the server. The CVSS v3.1 base score of 9.9 (AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H) reflects its critical severity, enabling network-accessible attacks with low complexity that can achieve high confidentiality, integrity, and availability impacts through scope expansion.

The vulnerability is addressed in Signal K Server version 1.5.0. Additional details are available in the GitHub security advisory at https://github.com/SignalK/signalk-server/security/advisories/GHSA-p8gp-2w28-mhwg and the fixing commit at https://github.com/SignalK/set-system-time/commit/75b11eae2de528bf89ede3fb1f7ed057ddbb4d24.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Signal K Server is a server application that runs on a central hub in a boat. Prior to 1.5.0, a command injection vulnerability allows authenticated users with write permissions to execute arbitrary shell commands on the Signal K server when…

more

the set-system-time plugin is enabled. Unauthenticated users can also exploit this vulnerability if security is disabled on the Signal K server. This occurs due to unsafe construction of shell commands when processing navigation.datetime values received via WebSocket delta messages. This vulnerability is fixed in 1.5.0.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-66398Same product: Signalk Signal K Server
CVE-2025-68619Same product: Signalk Signal K Server
CVE-2025-68620Same product: Signalk Signal K Server
CVE-2026-34083Same product: Signalk Signal K Server
CVE-2026-33950Same product: Signalk Signal K Server
CVE-2026-33951Same product: Signalk Signal K Server
CVE-2026-35038Same product: Signalk Signal K Server
CVE-2025-68272Same product: Signalk Signal K Server
CVE-2025-68273Same product: Signalk Signal K Server
CVE-2026-39320Same product: Signalk Signal K Server

Affected Assets

signalk
signal k server
≤ 1.5.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.2.5
  • V1.2.8
  • V15.2.5

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover missing or incorrect command sanitization during development.

Input validation directly neutralizes or rejects special characters that would otherwise alter OS command structure.

Least privilege reduces the permissions available to any process that could be subverted by injected commands.

Least functionality restricts available OS commands and interpreters, limiting the blast radius of injection.

Secure engineering principles require proper neutralization of untrusted input before command construction.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.

PR.PS-02 partial match
prevents

Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.

References