Describe CVE-2018-4838.
What is CVE-2018-4838?
A vulnerability has been identified in EN100 Ethernet module IEC 61850 variant (All versions < V4.30), EN100 Ethernet module DNP3 variant (All versions < V1.04), EN100 Ethernet module PROFINET IO variant (All versions), EN100 Ethernet module Modbus TCP variant (All versions), EN100 Ethernet module IEC 104 variant (All versions < V1.22). The web interface (TCP/80) of affected devices allows an unauthenticated user to upgrade or downgrade the firmware of the device, including to older versions with known vulnerabilities..