This indicates an attack attempt against a Buffer Overflow vulnerability in Procyon Core Server.
The vulnerability is caused by an error when the software handles specially a crafted HMI LOGON Request. It allows a remote attacker to execute arbitrary code.
Scadatec Procyon 1.13 or earlier.
System Compromise: Remote attackers can gain control of vulnerable systems.
Refer to the vendor's website for a suggested workaround.