WAGO: Multiple Vulnerabilities in I/O-Check Service

A missing authentication vulnerability exists in the iocheckd service "I/O-Check" functionality. A single packet can cause a denial of service and weaken credentials resulting in the default documented credentials being applied to the device. An attacker can send an unauthenticated packet to trigger this vulnerability.

The reported vulnerability enables a remote attacker to send arbitrary commands without authentication. This could result in changes to settings, application deletion, factory resets, code execution, system crashes or denial of service. By using specially crafted IP packets, the attacker can manipulate settings and disrupt the device's basic functions, potentially gaining control of the device.

The I/O-Check service protocol is only needed during installation and commissioning, not during normal operations. It is highly recommended to disable the IP-port 6626 after commissioning.