An exploitable stack buffer overflow vulnerability exists in the command line utility getcouplerdetails of WAGO PFC200 Firmware versions 03.01.07(13) and 03.00.39(12), and WAGO PFC100 Firmware version 03.00.39(12). A specially crafted set of packets sent to the iocheckd service "I/O-Check" can cause a stack buffer overflow in the sub-process getcouplerdetails, resulting in code execution. An attacker can send unauthenticated packets to trigger this vulnerability.