PT-2018-05: Unauthorized Firmware Modification in Siemens EN100 Ethernet modules

(PT-2018-05) Positive Technologies Security Advisory
Unauthorized Firmware Modification in Siemens EN100 Ethernet modules

Vulnerable products

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


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


The vulnerability was detected by Ilya Karpov and Alexey Stennikov, Positive Research Center (Positive Technologies Company)


Reports on the vulnerabilities previously discovered by Positive Research:

About Positive Technologies

Positive Technologies is a leading provider of vulnerability assessment, compliance management and threat analysis solutions to more than 1,000 global enterprise clients. Our solutions work seamlessly across your entire business: securing applications in development; assessing your network and application vulnerabilities; assuring compliance with regulatory requirements; and blocking real-time attacks. Our commitment to clients and research has earned Positive Technologies a reputation as one of the foremost authorities on SCADA, Banking, Telecom, Web Application and ERP security, and distinction as the #1 fastest growing Security and Vulnerability Management firm in 2012, as shown in an IDC report*. To learn more about Positive Technologies please visit

*Source: IDC Worldwide Security and Vulnerability Management 2013-2017 Forecast and 2012 Vendor Shares, doc #242465, August 2013. Based on year-over-year revenue growth in 2012 for vendors with revenues of $20M+