CVE-2025-69970: FUXA Authentication Bypass Vulnerability

CVE-2025-69970 Overview

CVE-2025-69970 is an insecure default configuration vulnerability discovered in FUXA v1.2.7, an open-source web-based SCADA/HMI platform used for industrial automation and process visualization. The vulnerability exists in server/settings.default.js where the secureEnabled flag is commented out by default, causing the application to initialize with authentication disabled. This critical security flaw allows unauthenticated remote attackers to access sensitive API endpoints, modify projects, and control industrial equipment immediately after installation.

Critical Impact

Unauthenticated attackers can remotely access and control industrial equipment, modify SCADA/HMI projects, and access sensitive API endpoints without any authentication credentials immediately upon FUXA installation.

Affected Products

• FUXA v1.2.7
• FUXA installations using default server/settings.default.js configuration
• Industrial SCADA/HMI systems running vulnerable FUXA versions

Discovery Timeline

• 2026-02-03 - CVE CVE-2025-69970 published to NVD
• 2026-02-05 - Last updated in NVD database

Technical Details for CVE-2025-69970

Vulnerability Analysis

This vulnerability represents a classic insecure default configuration flaw in industrial control system software. FUXA, designed for SCADA (Supervisory Control and Data Acquisition) and HMI (Human-Machine Interface) applications, ships with authentication controls disabled by default. The secureEnabled configuration option in server/settings.default.js is commented out, meaning fresh installations immediately expose all functionality without requiring user authentication.

The impact is particularly severe given FUXA's role in industrial environments. Attackers exploiting this vulnerability can interact with connected PLCs (Programmable Logic Controllers), modify visualization dashboards, access process data, and potentially manipulate physical industrial equipment. The network-accessible nature of the vulnerability means any system reachable over the network is immediately at risk.

Root Cause

The root cause stems from a security-by-default design failure in the FUXA configuration file. The secureEnabled flag that controls authentication enforcement is commented out in the default settings template (server/settings.default.js). When the application initializes without explicit security configuration, it defaults to an insecure state with authentication disabled. This "open by default" approach prioritizes ease of initial setup over security, leaving administrators unaware that their installation is immediately accessible to anyone on the network.

Attack Vector

The attack vector is network-based and requires no authentication. An attacker can exploit this vulnerability by:

1. Identifying FUXA installations through network scanning or Shodan-style reconnaissance for exposed SCADA/HMI interfaces
2. Accessing the FUXA web interface directly without credentials
3. Interacting with unprotected API endpoints to enumerate projects, configurations, and connected devices
4. Modifying project configurations to alter industrial process visualizations or control logic
5. Potentially sending commands to connected industrial equipment through the HMI interface

The vulnerability requires user interaction only in the sense that an administrator must have deployed FUXA with default settings. Technical details regarding the vulnerable configuration can be reviewed in the GitHub FUXA Configuration File.

Detection Methods for CVE-2025-69970

Indicators of Compromise

• Unexpected or unauthorized API requests to FUXA endpoints from external IP addresses
• Configuration changes to FUXA projects without corresponding administrator activity
• Audit logs showing anonymous access to protected resources or administrative functions
• Network traffic to FUXA services from untrusted sources or geographic regions

Detection Strategies

• Monitor FUXA application logs for authentication bypass patterns or anonymous session activity
• Implement network intrusion detection rules to identify unauthenticated access attempts to FUXA API endpoints
• Deploy web application firewalls (WAF) to detect and block suspicious requests targeting SCADA/HMI interfaces
• Conduct regular configuration audits to verify secureEnabled is properly set to true

Monitoring Recommendations

• Enable verbose logging on FUXA instances and centralize logs for security analysis
• Implement alerting for any access to FUXA management interfaces from non-whitelisted IP addresses
• Monitor for reconnaissance activity targeting common SCADA/HMI ports and services
• Track configuration file changes on FUXA servers using file integrity monitoring

How to Mitigate CVE-2025-69970

Immediate Actions Required

• Review the server/settings.default.js configuration file and uncomment the secureEnabled flag, setting it to true
• Implement strong authentication credentials for all FUXA user accounts
• Restrict network access to FUXA installations using firewalls and network segmentation
• Audit existing FUXA deployments for evidence of unauthorized access or configuration changes

Patch Information

Organizations should review the official FUXA repository for configuration guidance and any security updates. The primary mitigation involves enabling authentication by properly configuring the secureEnabled parameter. Administrators should consult the GitHub FUXA Configuration File for the correct configuration syntax and ensure authentication is enforced before exposing FUXA to any network.

Workarounds

• Place FUXA installations behind a VPN or reverse proxy with mandatory authentication
• Implement network-level access controls to restrict FUXA access to authorized management workstations only
• Deploy FUXA in isolated network segments with no direct internet exposure
• Use host-based firewalls to limit inbound connections to FUXA services from trusted sources only

# Configuration example - Enable authentication in FUXA
# Edit server/settings.default.js and ensure secureEnabled is set:
# secureEnabled: true

# Restrict network access using iptables (example)
iptables -A INPUT -p tcp --dport 1881 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 1881 -j DROP