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.
https://www.securityfocus.com/bid/103379
https://ics-cert.us-cert.gov/advisories/ICSA-18-067-01
https://cert-portal.siemens.com/productcert/pdf/ssa-845879.pdf