NovaTech Orion Substation Automation Platform OrionLX DNP Master 1.27.38 and DNP Slave 1.23.10 and earlier and Orion5/Orion5r DNP Master 1.27.38 and DNP Slave 1.23.10 and earlier allow physically proximate attackers to cause a denial of service (driver crash and process restart) via crafted input over a serial line.