This indicates an attack attempt to exploit a Buffer Overflow vulnerability in Delta Controls enteliBUS Manager (eBMGR).
A remote, unauthenticated attacker can exploit this vulnerability by sending a crafted BACnet packet to the vulnerable device. Successful exploitation can result in arbitrary code execution.
Delta Controls enteliBUS Manager firmware v1_V3.40_B-571848
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply patch available from the vendor (requires customer account):