PT-2018-05: Unauthorized Firmware Modification in Siemens EN100 Ethernet modules Vulnerable products DIGSI 4 Version: 4.91 and earlier EN100 Ethernet module IEC 61850 Version: 4.29 and earlier EN100 Ethernet module PROFINET IO Version: all vesions EN100 Ethernet module Modbus TCP Version: all vesions EN100 Ethernet module DNP3 Version: all vesions EN100 Ethernet module IEC 104 Version: all vesions Link: https://www.siemens.com/ Severity level Severity level: High Impact: Unauthorized Firmware Modification Access Vector: Remote CVSS v3: Base Score: 7.5 Vector: (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N) CVE: CVE-2018-4838 Vulnerability description The specialists of the Positive Research center have detected an Unauthorized Firmware Modification vulnerability in Siemens EN100 Ethernet modules. Vulnerability allows unauthenticated attackers to upgrade or downgrade the firmware of the affected device (including to older versions with known vulnerabilities) via its web interface (TCP/80). How to fix Update firmware to the latest version or use the vendor's recommendations Advisory status 17.12.2015 - Vendor gets vulnerability details 08.03.2018 - Vendor releases fixed version and details 30.03.2018 - Public disclosure Credits The vulnerability was detected by Ilya Karpov and Alexey Stennikov, Positive Research Center (Positive Technologies Company) References http://en.securitylab.ru/lab/PT-2018-05 https://ics-cert.us-cert.gov/advisories/ICSA-18-067-02 https://cert-portal.siemens.com/productcert/pdf/ssa-845879.pdf Reports on the vulnerabilities previously discovered by Positive Research: https://www.ptsecurity.com/ https://en.securitylab.ru/lab/ About Positive Technologies Positive Technologies is a leading digital security firm with over 15 years of experience in 360° protection of critical IT systems against the most advanced cyberthreats. State-of-the-art solutions are developed at the company's research center—one of the largest in Europe. Positive Technologies experts have helped to identify and fix over 250 zero-day vulnerabilities in products from Cisco, Google, Honeywell, Huawei, Microsoft, Oracle, SAP, Schneider Electric, Siemens, and others, earning a reputation for world-class expertise in protection of devices and infrastructures at all scales from ATMs to nuclear power stations. Findings by Positive Technologies researchers are used for updating the MaxPatrol knowledge base and for development of security solutions including PT Application Firewall, PT Application Inspector, MaxPatrol. These products allow securing web applications, evaluating network protection, blocking attacks in real time, ensuring compliance with industry and national standards, and training security specialists. Positive Technologies is the organizer of the annual Positive Hack Days international forum and security competition.