CVE-2026-4769

Name of the Vulnerable Software and Affected Versions WAGO System I/O Field series (affected versions not specified)

Description Certain devices activate an undocumented internal diagnostic capability during the initial startup sequence. This functionality is accessible without authentication for a brief period during the early boot phase because authentication is not enforced until later services initialize. An unauthenticated remote attacker on the same network can time requests during this window, such as immediately after a power-cycle or reboot, to interact with internal system processes. This can lead to full system compromise, allowing remote control of the device and potential disruption of industrial operations.

Recommendations Restrict network access to the device and treat reboot events as high-risk until a patch is applied. At the moment, there is no information about a newer version that contains a fix for this vulnerability.