(PT-2018-03) Positive Technologies Security Advisory
Control Takeover in Siemens DIGSI 4 and 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: Control Takeover
Access Vector: Remote

CVSS v3:
Base Score: 10
Vector: (AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H)

CVE: CVE-2018-4840

Vulnerability description

The specialists of the Positive Research center have detected a Control Takeover vulnerability in Siemens DIGSI 4 and EN100 Ethernet modules.

Vulnerability allows unauthenticated remote, low-skilled attackers to upload a modified device configuration overwriting access authorization passwords, and obtain full control over the device.

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 Dmitry Sklyarov, Positive Research Center (Positive Technologies Company)

References

http://en.securitylab.ru/lab/PT-2018-03
https://ics-cert.us-cert.gov/advisories/ICSA-18-067-01
https://cert-portal.siemens.com/productcert/pdf/ssa-203306.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.