CVE-2026-47718: frangoteam FUXA authentication bypass in protected read APIs

Executive brief

FUXA, an open-source web-based SCADA/HMI system, contains a security flaw where its 'secure mode' fails to properly restrict access. Unauthorized users or those with invalid credentials can still view sensitive project data, system alarms, and scheduled tasks. This could allow an attacker to perform reconnaissance on industrial control systems or access proprietary project configurations.

Technical details

An authentication bypass exists in FUXA version 1.3.0-2773 due to improper token validation in 'server/api/jwt-helper.js'. The 'verifyToken()' function incorrectly treats missing or invalid JSON Web Tokens (JWT) as a 'guest' context rather than rejecting the request. When 'secureEnabled=true' is configured, API endpoints for projects, alarms, and the scheduler fail to verify if the guest context should be permitted, resulting in the disclosure of sensitive metadata to unauthenticated network attackers. This has been patched in version 1.3.1.

Affected products

• frangoteam FUXA 1.3.0-2773

Timeline

• 2026-05-26: patched: Version 1.3.1 released
• 2026-05-28: advisory: GitHub Advisory published

References

• https://api.github.com/users/north-echo
• https://github.com/north-echo
• https://api.github.com/users/north-echo/gists%7B/gist_id%7D
• https://api.github.com/users/north-echo/repos
• https://avatars.githubusercontent.com/u/122107484?v=4
• https://api.github.com/users/north-echo/events%7B/privacy%7D