TECSON/GOK Improper Authentication and Access Control on multiple devices

LX-Net
LX-Q-Net
e-litro net
SmartBox 4 LAN
SmartBox 4 LAN PRO

A security researcher discovered that the affected application doesn't properly restrict access to an endpoint that is responsible for saving settings, to a user with limited access rights. Based on the lack of adequately implemented access-control rules, by accessing a specific uniform resource locator (URL) on the web server, a malicious user is able to change the application settings without authenticating at all, which violates originally laid ACL rules.

This issue allows changing the configuration and get full access to the web-based configuration interface of the device wich includes all settings like passwords, alerting parameters and output states. That can adversely affect the planned operation of the equipment or can aid in further attacks on the industrial control process.

Temporary Fix / Mitigation:

In secure environments disable port forwarding and remote access to the device otherwise disable network access completely.

Solution:

Update the device to firmware V6.3.x or later to fix the vulnerability.

Maxim Rupp (rupp.it), coordinated by CERT@VDE (cert.vde.com)