# NAVTOR NavBox hard-coded SOAP credentials

Published: 2026-06-04 · Severity: routine · Sectors: infrastructure, technology
Canonical: https://vorant.io/reports/a241a002-4f5b-5bf5-857d-abe8ab262ff6/navtor-navbox-hard-coded-soap-credentials

> NAVTOR NavBox through 4.16.1.20 contains hard-coded WCF credentials allowing local attackers to bypass authentication and write files.

NAVTOR NavBox versions up to 4.16.1.20 contain hard-coded credentials within its Windows Communication Foundation (SOAP) implementation. If SOAP functionality is enabled, a local attacker can extract these credentials to authenticate against the WCF interface, bypassing the intended transfer workflow. Successful authentication grants access to privileged WCF methods, enabling file write or overwrite operations within application-defined paths. The vulnerability requires local access and has high attack complexity, making remote exploitation infeasible. NAVTOR released a patch in April 2026 (version 4.17.2.6 and later) that addresses this issue. NavBox systems with active connections will automatically update to the patched version without user intervention.

## Mentioned in this report

- Vulnerabilities: CVE-2026-21404

Source reporting: https://www.cisa.gov/news-events/ics-advisories/icsa-26-155-01

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