U.S. Flag Official website of the Department of Homeland Security
U.S. Department of Homeland Security Seal. ICS-CERT. Industrial Control Systems Cyber Emergency Response Team.
TLP:WHITE

Advisory (ICSA-18-163-02)

Siemens SCALANCE X Switches

Original release date: June 12, 2018

Legal Notice

All information products included in http://ics-cert.us-cert.gov are provided "as is" for informational purposes only. The Department of Homeland Security (DHS) does not provide any warranties of any kind regarding any information contained within. DHS does not endorse any commercial product or service, referenced in this product or otherwise. Further dissemination of this product is governed by the Traffic Light Protocol (TLP) marking in the header. For more information about TLP, see http://www.us-cert.gov/tlp/.



1. EXECUTIVE SUMMARY

  • CVSS v3 5.8
  • ATTENTION: Exploitable remotely
  • Vendor: Siemens
  • Equipment: SCALANCE X switches
  • Vulnerabilities: Cross-site Scripting

2. RISK EVALUATION

Successful exploitation of these cross-site scripting vulnerabilities could allow an attacker to store script code on the website and execute cross-site scripting (XSS), affecting the website’s confidentiality, integrity, and availability. However, no known public exploits specifically target these vulnerabilities. High skill level is needed to exploit.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

Siemens reports the vulnerabilities affects the following SCALANCE X switch products:

  • SCALANCE X-200: All versions prior to v5.2.3 (only affected by CVE-2018-4848),
  • SCALANCE X-200 IRT: All versions prior to v5.4.1, and
  • SCALANCE X300: All versions.

3.2 VULNERABILITY OVERVIEW

3.2.1    IMPROPER NEUTRALIZATION OF INPUT DURING WEB PAGE GENERATION ('CROSS-SITE SCRIPTING') CWE-79

A remote, authenticated attacker with access to the configuration web server could store script code on the website, provided the HRP redundancy option is set. This code could be executed in the web browser of users visiting this website (XSS), affecting its confidentiality, integrity, and availability.

User interaction is required for successful exploitation as the user needs to visit the manipulated website.

CVE-2018-4842 has been assigned to this vulnerability. A CVSS v3 base score of 5.5 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:L).

3.2.2    IMPROPER NEUTRALIZATION OF INPUT DURING WEB PAGE GENERATION ('CROSS-SITE SCRIPTING') CWE-79

The integrated configuration web server of the affected Scalance X switches could allow XSS attacks if unsuspecting users are tricked into accessing a malicious link.

User interaction is required for successful exploitation. The user must be logged into the web interface in order for the exploitation to succeed.

CVE-2018-4848 has been assigned to this vulnerability. A CVSS v3 base score of 5.8 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:L).

3.3 BACKGROUND

  • CRITICAL INFRASTRUCTURE SECTORS: Chemical, Energy, Food and Agriculture, Healthcare and Public Health, Transportation Systems, and Water and Wastewater Systems
  • COUNTRIES/AREAS DEPLOYED: Worldwide
  • COMPANY HEADQUARTERS LOCATION: Germany

3.4 RESEARCHER

Marius Rothenbücher and Ali Abbasi reported these vulnerabilities to Siemens Product CERT.

4. MITIGATIONS

Siemens has provided updates for the following products to fix the vulnerabilities:

  • SCALANCE X-200: Update to v5.2.3

https://support.industry.siemens.com/cs/cn/en/view/109758142

  • SCALANCE X-200 IRT: Update to v5.4.1

https://support.industry.siemens.com/cs/de/en/view/109758144

As a general security measure, Siemens strongly recommends protecting network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends configuring the environment according to Siemens’ operational guidelines for Industrial Security (Download: https://www.siemens.com/cert/operational-guidelines-industrial-security), and following the recommendations in the product manuals.

Additional information on Industrial Security by Siemens can be found at:

https://www.siemens.com/industrialsecurity

For more information on these vulnerabilities and associated software updates, please see Siemens security advisory SSA-480829 on their website:

https://www.siemens.com/cert/advisories

NCCIC reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.

NCCIC also provides a section for control systems security recommended practices on the ICS-CERT web page. Several recommended practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.

Additional mitigation guidance and recommended practices are publicly available on the ICS-CERT website in the Technical Information Paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies.

Organizations observing any suspected malicious activity should follow their established internal procedures and report their findings to NCCIC for tracking and correlation against other incidents.

NCCIC also recommends that users take the following measures to protect themselves from social engineering attacks:

No known public exploits specifically target these vulnerabilities. High skill level is needed to exploit.


Contact Information

For any questions related to this report, please contact the NCCIC at:

Email: NCCICCUSTOMERSERVICE@hq.dhs.gov
Toll Free: 1-888-282-0870

For industrial control systems cybersecurity information:  http://ics-cert.us-cert.gov 
or incident reporting:  https://ics-cert.us-cert.gov/Report-Incident?

The NCCIC continuously strives to improve its products and services. You can help by choosing one of the links below to provide feedback about this product.

Was this document helpful?  Yes  |  Somewhat  |  No

Back to Top